Data Binding in Blazor DataGrid Component
29 May 202424 minutes to read
The DataGrid uses SfDataManager, which supports both RESTful JSON data services binding and IEnumerable binding. The DataSource value can be assigned either with the property values from SfDataManager or list of business objects.
It supports the following kinds of data binding method:
- List binding
- Remote data
NOTE
When using DataSource as
IEnumerable<T>, component type(TValue) will be inferred from its value. When using SfDataManager for data binding then the TValue must be provided explicitly in the datagrid component.
List binding
To bind list binding to the datagrid, you can assign a IEnumerable object to the DataSource property. The list data source can also be provided as an instance of the SfDataManager or by usingSfDataManager component.
@using Syncfusion.Blazor.Grids
<SfGrid DataSource="@Orders" AllowPaging="true">
<GridPageSettings PageSize="5"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText="Order Date" Format="d" Type="ColumnType.DateOnly" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.OrderTime) HeaderText="Order Time" Type="ColumnType.TimeOnly" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 10).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
OrderDate = new DateOnly(2023, 2, x),
OrderTime = new TimeOnly(x, 00)
}).ToList();
}
public class Order {
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateOnly? OrderDate { get; set; }
public TimeOnly? OrderTime { get; set; }
public double? Freight { get; set; }
}
}NOTE
By default, SfDataManager uses BlazorAdaptor for list data-binding.
ExpandoObject binding
Grid is a generic component which is strongly bound to a model type. There are cases when the model type is unknown during compile type. In such cases you can bound data to the grid as list of ExpandoObject.
To know about ExpandoObject data binding in Blazor DataGrid component, you can check on this video.
ExpandoObject can be bound to datagrid by assigning to the DataSource property. Grid can also perform all kind of supported data operations and editing in ExpandoObject.
@using Syncfusion.Blazor.Grids
@using System.Dynamic
<SfGrid DataSource="@Orders" AllowPaging="true" Toolbar="@ToolbarItems">
<GridEditSettings AllowAdding="true" AllowDeleting="true" AllowEditing="true"></GridEditSettings>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="CustomerID" HeaderText="Customer Name" Width="120"></GridColumn>
<GridColumn Field="Freight" HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="OrderDate" HeaderText=" Order Date" Format="d" TextAlign="TextAlign.Right" Width="130" Type="ColumnType.Date"></GridColumn>
<GridColumn Field="ShipCountry" HeaderText="Ship Country" EditType="EditType.DropDownEdit" Width="150"></GridColumn>
<GridColumn Field="Verified" HeaderText="Active" DisplayAsCheckBox="true" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code {
public List<ExpandoObject> Orders { get; set; } = new List<ExpandoObject>();
private List<string> ToolbarItems = new List<string>() { "Add", "Edit", "Delete", "Update", "Cancel" };
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select((x) =>
{
dynamic d = new ExpandoObject();
d.OrderID = 1000 + x;
d.CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)];
d.Freight = (new double[] { 2, 1, 4, 5, 3 })[new Random().Next(5)] * x;
d.OrderDate = (new DateTime[] { new DateTime(2010, 11, 5), new DateTime(2018, 10, 3), new DateTime(1995, 9, 9), new DateTime(2012, 8, 2), new DateTime(2015, 4, 11) })[new Random().Next(5)];
d.ShipCountry = (new string[] { "USA", "UK" })[new Random().Next(2)];
d.Verified = (new bool[] { true, false })[new Random().Next(2)];
return d;
}).Cast<ExpandoObject>().ToList<ExpandoObject>();
}
}ExpandoObject Complex data binding
You can achieve ExpandoObject complex data binding in the datagrid by using the dot(.) operator in the column.field. In the following examples, CustomerID.Name and ShipCountry.Country are complex data.
@using Syncfusion.Blazor.Grids
@using System.Dynamic
<SfGrid DataSource="@Orders" AllowPaging="true" AllowFiltering="true" AllowSorting="true" AllowGrouping="true" Toolbar="@ToolbarItems">
<GridEditSettings AllowAdding="true" AllowDeleting="true" AllowEditing="true"></GridEditSettings>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="CustomerID.Name" HeaderText="Customer Name" Width="120"></GridColumn>
<GridColumn Field="Freight" HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="OrderDate" HeaderText=" Order Date" Format="d" TextAlign="TextAlign.Right" Width="130" Type="ColumnType.Date"></GridColumn>
<GridColumn Field="ShipCountry.Country" HeaderText="Ship Country" Width="150"></GridColumn>
<GridColumn Field="Verified" HeaderText="Active" DisplayAsCheckBox="true" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code {
public List<ExpandoObject> Orders { get; set; } = new List<ExpandoObject>();
private List<string> ToolbarItems = new List<string>() { "Add", "Edit", "Delete", "Update", "Cancel" };
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select((x) =>
{
dynamic d = new ExpandoObject();
dynamic customerName = new ExpandoObject();
dynamic countryName = new ExpandoObject();
d.OrderID = 1000 + x;
customerName.Name = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)];
d.CustomerID = customerName;
d.Freight = (new double[] { 2, 1, 4, 5, 3 })[new Random().Next(5)] * x;
d.OrderDate = (new DateTime[] { new DateTime(2010, 11, 5), new DateTime(2018, 10, 3), new DateTime(1995, 9, 9), new DateTime(2012, 8, 2), new DateTime(2015, 4, 11) })[new Random().Next(5)];
countryName.Country = (new string[] { "USA", "UK" })[new Random().Next(2)];
d.ShipCountry = countryName;
d.Verified = (new bool[] { true, false })[new Random().Next(2)];
return d;
}).Cast<ExpandoObject>().ToList<ExpandoObject>();
}
}NOTE
You can perform the Data operations and CRUD operations for Complex ExpandoObject binding fields too.
The following image represents ExpandoObject complex data binding,
DynamicObject binding
Grid is a generic component which is strongly bound to a model type. There are cases when the model type is unknown during compile type. In such cases you can bound data to the grid as list of DynamicObject.
To know about DynamicObject data binding in Blazor DataGrid component, you can check on this video.
DynamicObject can be bound to datagrid by assigning to the DataSource property. Grid can also perform all kind of supported data operations and editing in DynamicObject.
NOTE
The GetDynamicMemberNames method of DynamicObject class must be overridden and return the property names to perform data operation and editing while using DynamicObject.
@using Syncfusion.Blazor.Grids
@using System.Dynamic
<SfGrid DataSource="@Orders" AllowPaging="true" Toolbar="@ToolbarItems">
<GridEditSettings AllowAdding="true" AllowDeleting="true" AllowEditing="true"></GridEditSettings>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="CustomerID" HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field="OrderDate" HeaderText="Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" EditType="EditType.DatePickerEdit" Width="130"></GridColumn>
<GridColumn Field="Freight" HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code {
private List<string> ToolbarItems = new List<string>(){ "Add","Edit","Delete","Update","Cancel"};
public List<DynamicDictionary> Orders = new List<DynamicDictionary>() { };
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 1075).Select((x) =>
{
dynamic d = new DynamicDictionary();
d.OrderID = 1000 + x;
d.CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)];
d.Freight = (new double[] { 2, 1, 4, 5, 3 })[new Random().Next(5)] * x;
d.OrderDate = DateTime.Now.AddDays(-x);
return d;
}).Cast<DynamicDictionary>().ToList<DynamicDictionary>();
}
public class DynamicDictionary : DynamicObject
{
Dictionary<string, object> dictionary = new Dictionary<string, object>();
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
string name = binder.Name;
return dictionary.TryGetValue(name, out result);
}
public override bool TrySetMember(SetMemberBinder binder, object value)
{
dictionary[binder.Name] = value;
return true;
}
public override System.Collections.Generic.IEnumerable<string> GetDynamicMemberNames()
{
return this.dictionary?.Keys;
}
}
}DynamicObject Complex data binding
You can achieve DynamicObject complex data binding in the datagrid by using the dot(.) operator in the column.field. In the following examples, CustomerID.Name and ShipCountry.Country are complex data.
@using Syncfusion.Blazor.Grids
@using System.Dynamic
<SfGrid DataSource="@Orders" AllowPaging="true" AllowFiltering="true" AllowSorting="true" AllowGrouping="true" Toolbar="@ToolbarItems">
<GridEditSettings AllowAdding="true" AllowDeleting="true" AllowEditing="true"></GridEditSettings>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="CustomerID.Name" HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field="OrderDate" HeaderText="Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" EditType="EditType.DatePickerEdit" Width="130"></GridColumn>
<GridColumn Field="Freight" HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="ShipCountry.Country" HeaderText="Ship Country" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code {
private List<string> ToolbarItems = new List<string>() { "Add", "Edit", "Delete", "Update", "Cancel" };
public List<DynamicDictionary> Orders = new List<DynamicDictionary>() { };
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 1075).Select((x) =>
{
dynamic d = new DynamicDictionary();
dynamic combo = new DynamicDictionary();
dynamic countryName = new DynamicDictionary();
d.OrderID = 1000 + x;
combo.Name = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)];
d.CustomerID = combo;
d.Freight = (new double[] { 2, 1, 4, 5, 3 })[new Random().Next(5)] * x;
d.OrderDate = DateTime.Now.AddDays(-x);
countryName.Country = (new string[] { "USA", "UK" })[new Random().Next(2)];
d.ShipCountry = countryName;
return d;
}).Cast<DynamicDictionary>().ToList<DynamicDictionary>();
}
public class DynamicDictionary : DynamicObject
{
Dictionary<string, object> dictionary = new Dictionary<string, object>();
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
string name = binder.Name;
return dictionary.TryGetValue(name, out result);
}
public override bool TrySetMember(SetMemberBinder binder, object value)
{
dictionary[binder.Name] = value;
return true;
}
public override System.Collections.Generic.IEnumerable<string> GetDynamicMemberNames()
{
return this.dictionary?.Keys;
}
}
}NOTE
- you can perform the Data operations and CRUD operations for Complex DynamicObject binding fields too.
The following image represents DynamicObject complex data binding
NOTE
While binding the Grid DataSource dynamically in the form of a list of IEnumerable collections, you need to call the Refresh() method of the Grid to reflect the changes externally. Because tracking items of IEnumerable for changes made externally is avoided for performance considerations.
DataTable binding
DataTable represents a table with data rows and columns. Data binding of the DataTable can be achieved in the DataGrid component by providing the CustomAdaptor class and overriding the Read or ReadAsync method of the DataAdaptor abstract class.
To bind DataTable to the datagrid, you can assign TValue to the ExpandoObject.
Refer to the following code example for how to bind the DataTable using custom adaptor.
@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
@using System.Dynamic;
@using System.Data;
<SfGrid TValue="ExpandoObject" ID="Grid" AllowSorting="true" AllowPaging="true" AllowFiltering="true" Toolbar="@(new List<string>() { "Search" })">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" ValidationRules="@(new ValidationRules{ Required=true, Number=true})" Width="120"></GridColumn>
<GridColumn Field="CustomerID" HeaderText="Customer Name" ValidationRules="@(new ValidationRules { Required=true})" Width="150"></GridColumn>
<GridColumn Field="OrderDate" HeaderText="Order Date" Format="d" Type="ColumnType.Date" Width="130"></GridColumn>
<GridColumn Field="EmployeeID" HeaderText="Employee ID" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code {
public static DataTable dataTable { get; set; }
public static IQueryable DataSource;
protected override void OnInitialized()
{
dataTable = GetData();
DataSource = ToQueryableCollection(dataTable); // Convert DataTable to IQueryable ExpandoObject list
}
// Implementing custom adaptor by extending the DataAdaptor class
public class CustomAdaptor : DataAdaptor
{
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
// Performs Searching, Sorting, Filtering
DataSource = PerformDataOperation(dataTable, dm);
int count = DataSource.Cast<ExpandoObject>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = QueryableOperation.PerformSkip<object>((IQueryable<object>)DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = QueryableOperation.PerformTake<object>((IQueryable<object>)DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
// Performs data operations like Searching, Sorting, and Filtering
public static IQueryable PerformDataOperation(DataTable dt, DataManagerRequest dm)
{
// Convert DataTable to IQueryable collection of datasource
DataSource = ToQueryableCollection(dt);
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DynamicObjectOperation.PerformSearching(DataSource, dm.Search);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DynamicObjectOperation.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DynamicObjectOperation.PerformSorting(DataSource, dm.Sorted);
}
return DataSource;
}
// This method converts the DataTable data source into an IQueryable collection data source.
public static IQueryable ToQueryableCollection(DataTable dt)
{
List<ExpandoObject> expandoList = new List<ExpandoObject>();
foreach (DataRow row in dt.Rows)
{
var expandoDict = new ExpandoObject() as IDictionary<String, Object>;
foreach (DataColumn col in dt.Columns)
{
var colValue = row[col.ColumnName];
colValue = (colValue == DBNull.Value) ? null : colValue;
expandoDict.Add(col.ToString(), colValue);
}
expandoList.Add((ExpandoObject)expandoDict);
}
return expandoList.AsQueryable();
}
public DataTable GetData()
{
DataTable dt = new DataTable();
dt.Columns.AddRange(new DataColumn[4] { new DataColumn("OrderID", typeof(long)),
new DataColumn("CustomerID", typeof(string)),
new DataColumn("EmployeeID",typeof(int)),
new DataColumn("OrderDate",typeof(DateTime))
});
int code = 1000;
int id = 0;
for (int i = 1; i <= 15; i++)
{
dt.Rows.Add(code + 1, "ALFKI", id + 1, new DateTime(1991, 05, 15));
dt.Rows.Add(code + 2, "ANATR", id + 2, new DateTime(1990, 04, 04));
dt.Rows.Add(code + 3, "ANTON", id + 3, new DateTime(1957, 11, 30));
dt.Rows.Add(code + 4, "BLONP", id + 4, new DateTime(1930, 10, 22));
dt.Rows.Add(code + 5, "BOLID", id + 5, new DateTime(1953, 02, 18));
code += 5;
id += 5;
}
return dt;
}
}In the above example, DataTable is passed to the ToQueryableCollection method, which converts the DataTable datasource into an IQueryable collection datasource.
You can perform data operations like searching, sorting and filtering using the PerformDataOperation method. This method takes a DataTable and a DataManagerRequest object as parameters, processes the data operations, and then returns an IQueryable data source.
Refer to the following code example for how to implement grouping and aggregates in a DataTable using a custom adaptor.
// Implementing custom adaptor by extending the DataAdaptor class
public class CustomAdaptor : DataAdaptor
{
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
// Convert DataTable to IQueryable ExpandoObject list
DataSource = ToQueryableCollection(dataTable);
int count = DataSource.Cast<ExpandoObject>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = QueryableOperation.PerformSkip<object>((IQueryable<object>)DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = QueryableOperation.PerformTake<object>((IQueryable<object>)DataSource, dm.Take);
}
// Aggregation
IDictionary<string, object> aggregates = new Dictionary<string, object>();
if (dm.Aggregates != null)
{
aggregates = DataUtil.PerformAggregation(DataSource, dm.Aggregates);
}
// Grouping
DataResult DataObject = new DataResult();
if (dm.Group != null)
{
IEnumerable result = (IEnumerable)DataSource;
foreach (var group in dm.Group)
{
result = DataUtil.Group<ExpandoObject>(result, group, dm.Aggregates, 0, dm.GroupByFormatter);
}
return dm.RequiresCounts ? new DataResult() { Result = result, Count = count, Aggregates = aggregates } : (object)DataSource;
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count, Aggregates = aggregates } : (object)DataSource;
}
}DataTable with CRUD operations
To perform CRUD operations for a DataTable, can be implemented by overriding the CRUD methods of the DataAdaptor abstract class.
- Insert/InsertAsync
- Remove/RemoveAsync
- Update/UpdateAsync
- BatchUpdate/BatchUpdateAsync
While using batch editing in DataGrid, use the BatchUpdate/BatchUpdateAsync method to handle the corresponding CRUD operations.
@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
@using System.Dynamic;
@using System.Data;
<SfGrid TValue="ExpandoObject" ID="Grid" AllowPaging="true" Toolbar="@(new List<string>() { "Add", "Delete", "Update", "Cancel" })">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridEditSettings AllowEditing="true" AllowDeleting="true" AllowAdding="true" Mode="@EditMode.Normal"></GridEditSettings>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" ValidationRules="@(new ValidationRules{ Required=true, Number=true})" Width="120"></GridColumn>
<GridColumn Field="CustomerID" HeaderText="Customer Name" ValidationRules="@(new ValidationRules { Required=true})" Width="150"></GridColumn>
<GridColumn Field="OrderDate" HeaderText="Order Date" Format="d" Type="ColumnType.Date" Width="130"></GridColumn>
<GridColumn Field="EmployeeID" HeaderText="Employee ID" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code {
public static DataTable dataTable { get; set; }
public static IQueryable DataSource;
protected override void OnInitialized()
{
dataTable = GetData();
DataSource = ToQueryableCollection(dataTable); // Convert DataTable to IQueryable ExpandoObject list
}
// Implementing custom adaptor by extending the DataAdaptor class
public class CustomAdaptor : DataAdaptor
{
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
// Performs Searching, Sorting, Filtering
DataSource = PerformDataOperation(dataTable, dm);
int count = DataSource.Cast<ExpandoObject>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = QueryableOperation.PerformSkip<object>((IQueryable<object>)DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = QueryableOperation.PerformTake<object>((IQueryable<object>)DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
//Performs Insert operation
public override object Insert(DataManager dm, object value, string key)
{
DataRow newRow = dataTable.NewRow();
var data = (ExpandoObject)value;
foreach (var item in data)
{
newRow[item.Key] = item.Value ?? DBNull.Value;
}
dataTable.Rows.InsertAt(newRow, 0);
return value;
}
//Performs Remove operation
public override object Remove(DataManager dm, object value, string keyField, string key)
{
DataRow? rowToRemove = null;
foreach (DataRow row in dataTable.Rows)
{
if (row[keyField].Equals(value))
{
rowToRemove = row;
break;
}
}
if (rowToRemove != null)
{
dataTable.Rows.Remove(rowToRemove);
}
return value;
}
// Performs Update operation
public override object Update(DataManager dm, object value, string keyField, string key)
{
var data = (IDictionary<string, object>)value;
var rowToUpdate = dataTable.Rows
.Cast<DataRow>()
.FirstOrDefault(row => row[keyField].Equals(data[keyField]));
if (rowToUpdate != null)
{
foreach (DataColumn column in dataTable.Columns)
{
var columnName = column.ColumnName;
var newValue = data[column.ColumnName] ?? column.DefaultValue;
rowToUpdate[columnName] = newValue;
}
}
return value;
}
// Performs BatchUpdate operation
public override object BatchUpdate(DataManager dm, object Changed, object Added, object Deleted, string KeyField, string Key, int? dropIndex)
{
if (Changed != null)
{
var changedRecords = (IEnumerable<IDictionary<string, object>>)Changed;
foreach (var record in changedRecords)
{
foreach (DataRow row in dataTable.Rows)
{
if (row[KeyField].Equals(record[KeyField]))
{
foreach (DataColumn column in dataTable.Columns)
{
row[column.ColumnName] = record[column.ColumnName] ?? column.DefaultValue;
}
}
}
}
}
if (Added != null)
{
var addedRecords = (IEnumerable<IDictionary<string, object>>)Added;
foreach (var record in addedRecords)
{
DataRow newRow = dataTable.NewRow();
foreach (var item in record)
{
newRow[item.Key] = item.Value ?? DBNull.Value;
}
dataTable.Rows.Add(newRow);
}
}
if (Deleted != null)
{
var deletedRecords = (IEnumerable<IDictionary<string, object>>)Deleted;
List<DataRow> rowsToRemove = new List<DataRow>();
foreach (var record in deletedRecords)
{
foreach (DataRow row in dataTable.Rows)
{
if (row[KeyField].Equals(record[KeyField]))
{
rowsToRemove.Add(row);
}
}
}
foreach (DataRow rowToRemove in rowsToRemove)
{
dataTable.Rows.Remove(rowToRemove);
}
}
return dataTable;
}
}
// Performs data operations like Searching, Sorting, and Filtering
public static IQueryable PerformDataOperation(DataTable dt, DataManagerRequest dm)
{
// Convert DataTable to IQueryable collection of datasource
DataSource = ToQueryableCollection(dt);
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DynamicObjectOperation.PerformSearching(DataSource, dm.Search);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DynamicObjectOperation.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DynamicObjectOperation.PerformSorting(DataSource, dm.Sorted);
}
return DataSource;
}
// This method converts the DataTable data source into an IQueryable collection data source.
public static IQueryable ToQueryableCollection(DataTable dt)
{
List<ExpandoObject> expandoList = new List<ExpandoObject>();
foreach (DataRow row in dt.Rows)
{
var expandoDict = new ExpandoObject() as IDictionary<String, Object>;
foreach (DataColumn col in dt.Columns)
{
var colValue = row[col.ColumnName];
colValue = (colValue == DBNull.Value) ? null : colValue;
expandoDict.Add(col.ToString(), colValue);
}
expandoList.Add((ExpandoObject)expandoDict);
}
return expandoList.AsQueryable();
}
public DataTable GetData()
{
DataTable dt = new DataTable();
dt.Columns.AddRange(new DataColumn[4] { new DataColumn("OrderID", typeof(long)),
new DataColumn("CustomerID", typeof(string)),
new DataColumn("EmployeeID",typeof(int)),
new DataColumn("OrderDate",typeof(DateTime))
});
int code = 1000;
int id = 0;
for (int i = 1; i <= 15; i++)
{
dt.Rows.Add(code + 1, "ALFKI", id + 1, new DateTime(1991, 05, 15));
dt.Rows.Add(code + 2, "ANATR", id + 2, new DateTime(1990, 04, 04));
dt.Rows.Add(code + 3, "ANTON", id + 3, new DateTime(1957, 11, 30));
dt.Rows.Add(code + 4, "BLONP", id + 4, new DateTime(1930, 10, 22));
dt.Rows.Add(code + 5, "BOLID", id + 5, new DateTime(1953, 02, 18));
code += 5;
id += 5;
}
return dt;
}
}Remote data
To bind remote data to datagrid component, assign service data as an instance of SfDataManager to the DataSource property or by using SfDataManager component. To interact with remote data source, provide the endpoint Url.
NOTE
When using SfDataManager for data binding then the TValue must be provided explicitly in the datagrid component.
By default, SfDataManager uses ODataAdaptor for remote data-binding.
Binding with OData services
OData is a standardized protocol for creating and consuming data. You can retrieve data from OData service using the SfDataManager. Refer to the following code example for remote Data binding using OData service.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging="true">
<SfDataManager Url="https://services.odata.org/Northwind/Northwind.svc/Orders" Adaptor="Adaptors.ODataAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.ShipCountry) HeaderText="Ship Country" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public class Order {
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
public string ShipCountry { get; set; }
}
}Binding with OData v4 services
The ODataV4 is an improved version of OData protocols, and the SfDataManager can also retrieve and consume OData v4 services. For more details on OData v4 services, refer to the OData documentation. To bind OData v4 service, use the ODataV4Adaptor.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging="true">
<SfDataManager Url="https://services.odata.org/V4/Northwind/Northwind.svc/Orders/" Adaptor="Adaptors.ODataV4Adaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public class Order {
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}Web API
You can use WebApiAdaptor to bind datagrid with Web API created using OData endpoint.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging="true">
<SfDataManager Url="https://blazor.syncfusion.com/services/production/api/Orders/" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public class Order {
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}The response object from the Web API should contain properties, Items and Count, whose values are a collection of entities and total count of the entities, respectively.
The sample response object should look like this:
{
Items: [{..}, {..}, {..}, ...],
Count: 830
}NOTE
The data source is returned in the form of items and count pairs while using the WebAPI Adaptor. But when the Offline property of SfDataManager is enabled, the entire data source is returned from the server as a collection of objects. So, the
$inlinecountwill not be present when theOfflineproperty is enabled. Also, only one request will be made to fetch the entire details from the server and no further request will be sent to the server.
Enable SfDataManager after initial rendering
It is possible to render the datasource in DataGrid after initial rendering. This can be achieved by conditionally enabling the SfDataManager component after datagrid rendering.
The following sample code demonstrates enabling data manager condition in the DataGrid on button click,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Buttons
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfButton OnClick="Enable" CssClass="e-primary" IsPrimary="true" Content="Enable data manager"></SfButton>
<SfGrid TValue="Order" AllowPaging="true">
<GridPageSettings PageSize="10"></GridPageSettings>
@if(IsInitialRender)
{
<SfDataManager Url="https://blazor.syncfusion.com/services/production/api/Orders/" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
}
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public bool IsInitialRender = false;
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
public void Enable()
{
// Enabling condition to render the data manager
this.IsInitialRender = true;
}
}The following GIF represents dynamically rendering data manager in DataGrid,
Sending additional parameters to the server
To add a custom parameter to the data request, use the addParams method of Query class. Assign the Query object with additional parameters to the datagrid’s Query property.
The following sample code demonstrates sending additional parameters using the Query property,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging="true" Query=@GridQuery>
<GridPageSettings PageSize="10"></GridPageSettings>
<SfDataManager Url="https://blazor.syncfusion.com/services/production/api/Orders/" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public string ParamValue = "true";
public Query GridQuery { get; set; }
protected override void OnInitialized() {
GridQuery = new Query().AddParams("ej2grid", ParamValue);
}
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}Configuring HttpClient
SfDataManager uses the HttpClient instance to make HTTP requests to data services. SfDataManager checks whether a HttpClient is already registered in the service container. If it’s found, the SfDataManager will use HttpClient from the service container else it will create and add HttpClient to the service container and use that instance for making requests to the server.
When registering your HttpClient, the registration should be done before calling AddSyncfusionBlazor() method in Program.cs, so that SfDataManager will not create its own HttpClient and uses the pre-configured HttpClient. This helps SfDataManager to use HttpClient instance pre-configured with base address, authentication, default headers, etc.
You could also pass HttpClient to the SfDataManager component as a parameter using HttpClientInstance property. This will be useful when the application has more than one pre-configured HttpClients. You can use this approach to use the named HttpClient with SfDataManager.
To troubleshoot the requests and responses made using HttpClient, a custom HTTP message handler can be used. More information about registering the custom HTTP message handler can be found here.
NOTE
Using Typed HttpClient with SfDataManager is not supported. The custom binding feature has to be used to achieve this requirement.
Handling HTTP error
During server interaction from the datagrid, sometimes server-side exceptions might occur. These error messages or exception details can be acquired in client-side using the OnActionFailure event.
The argument passed to the OnActionFailure event contains the error details returned from the server.
The following sample code demonstrates notifying user when server-side exception has occurred,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<span class="error">@ErrorDetails</span>
<SfGrid TValue="Order" AllowPaging="true">
<GridEvents TValue="Order" OnActionFailure="@ActionFailure"></GridEvents>
<GridPageSettings PageSize="10"></GridPageSettings>
<SfDataManager Url="https://some.com/invalidUrl" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
<style>
.error {
color: red;
}
</style>
@code{
public string ErrorDetails = "";
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
public void ActionFailure(FailureEventArgs args)
{
this.ErrorDetails = "Server exception: 404 Not found";
StateHasChanged();
}
}Authorization and Authentication
It is common to have authorization in the server of origin to prevent anonymous access to the data services. SfDataManager can consume data from such protected remote data services with the proper bearer token. The access token or bearer token can be used by SfDataManager in one of the following ways.
- By using the pre-configured HttpClient with the access token or authentication message handler, SfDataManager can access protected remote services. When registering your HttpClient, the registration should be done before calling
AddSyncfusionBlazor()method in Program.cs, so that SfDataManager will not create its own HttpClient and uses the already configured HttpClient. - Setting access token in the default header of the HttpClient by injecting it in the page. See here for adding default headers to HttpClient.
@inject HttpClient _httpClient
. . . .
@code {
. . .
protected override async Task OnInitializedAsync()
{
. . . .
_httpClient.DefaultRequestHeaders.Add("Authorization", $"Bearer {tokenValue}");
await base.OnInitializedAsync();
}
}- Setting the access token in the Headers property of the SfDataManager. See here for adding headers.
Getting the bearer token may vary with access token providers. More information on configuring HttpClient with authentication can be found on the official page here.
Setting custom headers
To add a custom headers to the data request, use the Headers property of the SfDataManager.
The following sample code demonstrates adding custom headers to the SfDataManager request,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging="true">
<GridPageSettings PageSize="10"></GridPageSettings>
<SfDataManager Headers=@HeaderData Url="https://blazor.syncfusion.com/services/production/api/Orders/" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
private IDictionary<string, string> HeaderData = new Dictionary<string, string>();
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}Change Query parameter value dynamically
It is possible to dynamically modify datagrid’s Query property value.
The following sample code demonstrates achieving this,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Buttons
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfButton Content="Modify query data" OnClick="BtnClick"></SfButton>
<SfGrid TValue="Order" @ref="GridObj" AllowPaging="true" Query="@QueryData">
<GridPageSettings PageSize="10"></GridPageSettings>
<SfDataManager Url="https://services.odata.org/V4/Northwind/Northwind.svc/Orders" Adaptor="Adaptors.ODataV4Adaptor">
</SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public SfGrid<Order> GridObj;
private Query QueryData = new Query().Where("CustomerID", "equal", "VINET");
private Query UpdatedQueryData = new Query().Where("CustomerID", "equal", "HANAR");
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public double? Freight { get; set; }
}
public void BtnClick()
{
QueryData = UpdatedQueryData;
}
}The following GIF represents dynamically modifying the query property in DataGrid,
GraphQL service binding
GraphQL is a query language for APIs with which you can get exactly what you need and nothing more. The GraphQLAdaptor provides an option to retrieve data from the GraphQL server. You can also perform CRUD and data operations like paging, sorting, filtering etc by sending the required arguments to the server.
Fetching data from GraphQL service and binding to grid
To bind GraphQL service data to grid, you have to provide the GraphQL query string by using the Query property of the GraphQLAdaptorOptions. Also you need to set the ResolverName property of GraphQLAdaptorOptions to map the response. The GraphQLAdaptor expects response as a JSON object with properties of Result, Count and Aggregates which contains the collection of entities, total number of records and value of aggregates respectively. The GraphQL response should be returned in JSON format like { “data”: { … }} with query name as field.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging=true AllowSorting=true AllowFiltering=true>
<SfDataManager Url="https://xxxxxx" GraphQLAdaptorOptions=@adaptorOptions Adaptor="Adaptors.GraphQLAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey=true TextAlign="TextAlign.Right" Width="120"><GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText="Order Date" Format="d" TextAlign="TextAlign.Right"
Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
private GraphQLAdaptorOptions adaptorOptions { get; set; } = new GraphQLAdaptorOptions
{
Query = @"
query ordersData($dataManager: DataManagerRequestInput!){
ordersData(dataManager: $dataManager) {
count, result { OrderID, CustomerID, OrderDate, Freight } , aggregates
}
}",
ResolverName = "OrdersData"
};
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}Performing data operations
The following code demonstrates the resolver function used in the GraphQL server to bind data and to perform data operations like paging, sorting, filtering etc.
public class GraphQLQuery
{
public ReturnType<Order> OrdersData(DataManagerRequest dataManager)
{
IEnumerable<Order> result = Orders;
if (dataManager.Search != null)
{
result = DataOperations.PerformSearching(result, dataManager.Search);
}
if (dataManager.Sorted != null)
{
result = DataOperations.PerformSorting(result, dataManager.Sorted);
}
if (dataManager.Where != null)
{
result = DataOperations.PerformFiltering<Order>(result.AsQueryable(), dataManager.Where, dataManager.Where[0].Condition).ToList();
}
int count = result.Count();
if (dataManager.Skip != 0)
{
result = DataOperations.PerformSkip(result, dataManager.Skip);
}
if (dataManager.Take != 0)
{
result = DataOperations.PerformTake(result, dataManager.Take);
}
if (dataManager.Aggregates != null)
{
IDictionary<string, object> aggregates = DataUtil.PerformAggregation(result, dataManager.Aggregates);
return new ReturnType<Order>() { Count = count, Result = result, Aggregates = aggregates };
}
return dataManager.RequiresCounts ? new ReturnType<Order>() { Result = result, Count = count } : new ReturnType<Order>() { Result = result };
}
public static List<Order> Orders { get; set; } = GetOrdersList();
private static List<Order> GetOrdersList()
{
var data = new List<Order>();
int count = 1000;
int employeeCount = 0;
for (int i = 0; i < 10; i++)
{
data.Add(new Order() { OrderID = count + 1, EmployeeID = employeeCount + 1, CustomerID = "ALFKI", OrderDate = new DateTime(2023, 08, 23), Freight = 5.7 * 2, Address = new CustomerAddress() { ShipCity = "Berlin", ShipCountry = "Denmark" } });
data.Add(new Order() { OrderID = count + 2, EmployeeID = employeeCount + 2, CustomerID = "ANANTR", OrderDate = new DateTime(1994, 08, 24), Freight = 6.7 * 2, Address = new CustomerAddress() { ShipCity = "Madrid", ShipCountry = "Brazil" } });
data.Add(new Order() { OrderID = count + 3, EmployeeID = employeeCount + 3, CustomerID = "BLONP", OrderDate = new DateTime(1993, 08, 25), Freight = 7.7 * 2, Address = new CustomerAddress() { ShipCity = "Cholchester", ShipCountry = "Germany" } });
data.Add(new Order() { OrderID = count + 4, EmployeeID = employeeCount + 4, CustomerID = "ANTON", OrderDate = new DateTime(1992, 08, 26), Freight = 8.7 * 2, Address = new CustomerAddress() { ShipCity = "Marseille", ShipCountry = "Austria" } });
data.Add(new Order() { OrderID = count + 5, EmployeeID = employeeCount + 5, CustomerID = "BOLID", OrderDate = new DateTime(1991, 08, 27), Freight = 9.7 * 2, Address = new CustomerAddress() { ShipCity = "Tsawassen", ShipCountry = "Switzerland" } });
count += 5;
employeeCount += 5;
}
return data;
}
}
public class ReturnType<T>
{
public int Count { get; set; }
public IEnumerable<T> Result { get; set; }
[GraphQLType(typeof(AnyType))]
public IDictionary<string, object> Aggregates { get; set; }
}Note
The implementation for PerformSearching, PerformSorting, PerformFiltering, PerformSkip, PerformTake, PerformAggregation methods can be found in the github sample.
Performing CRUD operation using mutation
You can perform the CRUD operations by setting the mutation queries in the Mutation property of GraphQLAdaptorOptions.
Normal editing and Dialog editing
The following sample code demonstrates performing CRUD operation by using Normal editing in grid. You have to set the Insert mutation query in Insert property of Mutation in GraphQLAdaptorOptions. Similarly, you have to set the Update and Delete mutation queries in Update and Delete properties of Mutation in GraphQLAdaptorOptions respectively.
If you want to use Dialog editing, then you can set the EditSettings.Mode as Dialog.
The following variables are passed as a parameter to the mutation method written for Insert operation in server side.
| Properties | Description |
|---|---|
| record | The new record which is need to be inserted. |
| index | Specifies the index at which the newly added record will be inserted. |
| action | Indicates the type of operation being performed. When the same method is used for all CRUD actions, this argument serves to distinguish the action, such as Add, Delete and Update |
| additionalParameters | An optional parameter that can be used to perform any operations. |
The following variables are passed as a parameter to the mutation method written for Update operation in server side.
| Properties | Description |
|---|---|
| record | The new record which is need to be updated. |
| action | Indicates the type of operation being performed. When the same method is used for all CRUD actions, this argument serves to distinguish the action, such as Add, Delete and Update |
| primaryColumnName | Specifies the field name of the primary column. |
| primaryColumnValue | Specifies the primary column value which is needs to be updated in the collection. |
| additionalParameters | An optional parameter that can be used to perform any operations. |
The following variables are passed as a parameter to the mutation method written for Delete operation in server side.
| Properties | Description |
|---|---|
| primaryColumnValue | Specifies the primary column value which is needs to be removed from the collection. |
| action | Indicates the type of operation being performed. When the same method is used for all CRUD actions, this argument serves to distinguish the action, such as Add, Delete and Update |
| primaryColumnName | specifies the field name of the primary column. |
| additionalParameters | An optional parameter that can be used to perform any operations. |
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging=true AllowSorting=true AllowFiltering=true
Toolbar="@(new List<string>() { "Search", "Add", "Edit", "Delete", "Cancel", "Update" })">
<GridEditSettings AllowAdding=true AllowEditing=true AllowDeleting=true Mode="EditMode.Normal"></GridEditSettings>
<SfDataManager Url="https://xxxxxx" GraphQLAdaptorOptions=@adaptorOptions Adaptor="Adaptors.GraphQLAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey=true TextAlign="TextAlign.Right" Width="120"><GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText="Order Date" Format="d" TextAlign="TextAlign.Right"
Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
private GraphQLAdaptorOptions adaptorOptions { get; set; } = new GraphQLAdaptorOptions
{
Query = @"
query ordersData($dataManager: DataManagerRequestInput!){
ordersData(dataManager: $dataManager) {
count, result { OrderID, CustomerID, OrderDate, Freight } , aggregates
}
}",
Mutation = new GraphQLMutation
{
Insert = @"
mutation create($record: OrderInput!, $index: Int!, $action: String!, $additionalParameters: Any) {
createOrder(order: $record, index: $index, action: $action, additionalParameters: $additionalParameters) {
OrderID, CustomerID, OrderDate, Freight
}
}",
Update = @"
mutation update($record: OrderInput!, $action: String!, $primaryColumnName: String! , $primaryColumnValue: Int!, $additionalParameters: Any) {
updateOrder(order: $record, action: $action, primaryColumnName: $primaryColumnName, primaryColumnValue: $primaryColumnValue, additionalParameters: $additionalParameters) {
OrderID, CustomerID, OrderDate, Freight
}
}",
Delete = @"
mutation delete($primaryColumnValue: Int!, $action: String!, $primaryColumnName: String!, $additionalParameters: Any) {
deleteOrder(primaryColumnValue: $primaryColumnValue, action: $action, primaryColumnName: $primaryColumnName, additionalParameters: $additionalParameters) {
OrderID, CustomerID, OrderDate, Freight
}
}"
},
ResolverName = "OrdersData"
};
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}The following code demonstrates the mutation methods used in the GraphQL server for Normal editing.
public class GraphQLMutation
{
public Order CreateOrder(Order order, int index, string action,
[GraphQLType(typeof(AnyType))] IDictionary<string, object> additionalParameters)
{
GraphQLQuery.Orders.Insert(index, order);
return order;
}
public Order UpdateOrder(Order order, string action, string primaryColumnName, int primaryColumnValue,
[GraphQLType(typeof(AnyType))] IDictionary<string, object> additionalParameters)
{
Order updatedOrder = GraphQLQuery.Orders.Where(x => x.OrderID == primaryColumnValue).FirstOrDefault();
updatedOrder.OrderID = order.OrderID;
updatedOrder.CustomerID = order.CustomerID;
updatedOrder.Freight = order.Freight;
updatedOrder.OrderDate = order.OrderDate;
return updatedOrder;
}
public Order DeleteOrder(int primaryColumnValue, string action, string primaryColumnName,
[GraphQLType(typeof(AnyType))] IDictionary<string, object> additionalParameters)
{
Order deletedOrder = GraphQLQuery.Orders.Where(x => x.OrderID == primaryColumnValue).FirstOrDefault();
GraphQLQuery.Orders.Remove(deletedOrder);
return deletedOrder;
}
}Batch editing
The following sample code demonstrates performing CRUD operation by using Batch editing in grid. You have to set the Batch mutation query in Batch property of Mutation in GraphQLAdaptorOptions.
The following variables are passed as a parameter to the mutation method written for Batch operation in server side.
| Properties | Description |
|---|---|
| changed | Specifies the collection of record to be updated. |
| added | Specifies the collection of record to be inserted. |
| deleted | Specifies the collection of record to be removed. |
| action | Indicates the type of operation being performed. |
| primaryColumnName | Specifies the field name of the primary column. |
| additionalParameters | An optional parameter that can be used to perform any operations. |
| dropIndex | Specifies the record position, from which new records will be added while performing drag and drop. |
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging=true AllowSorting=true AllowFiltering=true
Toolbar="@(new List<string>() { "Search", "Add", "Edit", "Delete", "Cancel", "Update" })">
<GridEditSettings AllowAdding=true AllowEditing=true AllowDeleting=true Mode="EditMode.Batch"></GridEditSettings>
<SfDataManager Url="https://xxxxxx" GraphQLAdaptorOptions=@adaptorOptions Adaptor="Adaptors.GraphQLAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey=true TextAlign="TextAlign.Right" Width="120"><GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText="Order Date" Format="d" TextAlign="TextAlign.Right"
Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
private GraphQLAdaptorOptions adaptorOptions { get; set; } = new GraphQLAdaptorOptions
{
Query = @"
query ordersData($dataManager: DataManagerRequestInput!){
ordersData(dataManager: $dataManager) {
count, result { OrderID, CustomerID, OrderDate, Freight } , aggregates
}
}",
Mutation = new GraphQLMutation
{
Batch = @"
mutation batch($changed: [OrderInput!], $added: [OrderInput!], $deleted: [OrderInput!], $action: String!, $primaryColumnName: String!, $additionalParameters: Any, $dropIndex: Int) {
batchUpdate(changed: $changed, added: $added, deleted: $deleted, action: $action, primaryColumnName :$primaryColumnName, additionalParameters: $additionalParameters, dropIndex: $dropIndex) {
OrderID, CustomerID, OrderDate, Freight
}
}"
},
ResolverName = "OrdersData"
};
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}The following code demonstrates the mutation method used in the GraphQL server for Batch editing.
public class GraphQLMutation
{
public List<Order> BatchUpdate(List<Order>? changed, List<Order>? added,
List<Order>? deleted, string action, String primaryColumnName,
[GraphQLType(typeof(AnyType))] IDictionary<string, object> additionalParameters, int? dropIndex)
{
if (changed != null && changed.Count > 0)
{
foreach (var changedOrder in (IEnumerable<Order>)changed)
{
Order order = GraphQLQuery.Orders.Where(e => e.OrderID == changedOrder.OrderID).FirstOrDefault();
order.OrderID = changedOrder.OrderID;
order.CustomerID = changedOrder.CustomerID;
order.OrderDate = changedOrder.OrderDate;
order.Freight = changedOrder.Freight;
}
}
if (added != null && added.Count > 0)
{
if (dropIndex != null)
{
//for Drag and Drop feature in Grid
GraphQLQuery.Orders.InsertRange((int)dropIndex, added);
}
else {
foreach (var newOrder in (IEnumerable<Order>)added)
{
GraphQLQuery.Orders.Add(newOrder);
}
}
}
if (deleted != null && deleted.Count > 0)
{
foreach (var deletedOrder in (IEnumerable<Order>)deleted)
{
GraphQLQuery.Orders.Remove(GraphQLQuery.Orders.Where(e => e.OrderID == deletedOrder.OrderID).FirstOrDefault());
}
}
return GraphQLQuery.Orders;
}
}Configuration in GraphQL server application
The following code is the configuration in GraphQL server application to set GraphQL query and mutation type and to enable CORS.
Program.cs
var builder = WebApplication.CreateBuilder(args);
//GraphQL resolver is defined in GraphQLQuery class and mutation methods are defined in GraphQLMutation class
builder.Services.AddGraphQLServer().AddQueryType<GraphQLQuery>().AddMutationType<GraphQLMutation>();
//CORS is enabled to access the GraphQL server from the client application
builder.Services.AddCors(options =>
{
options.AddPolicy("AllowSpecificOrigin", builder =>
{
builder.WithOrigins("https://xxxxxx")
.AllowAnyHeader()
.AllowAnyMethod()
.AllowCredentials().Build();
});
});The following code demonstrates the DataManagerRequest class which is passed as an argument to the resolver function.
public class DataManagerRequest
{
[GraphQLName("Skip")]
public int Skip { get; set; }
[GraphQLName("Take")]
public int Take { get; set; }
[GraphQLName("RequiresCounts")]
public bool RequiresCounts { get; set; } = false;
[GraphQLName("Params")]
[GraphQLType(typeof(AnyType))]
public IDictionary<string, object> Params { get; set; }
[GraphQLName("Aggregates")]
[GraphQLType(typeof(AnyType))]
public List<Aggregate>? Aggregates { get; set; }
[GraphQLName("Search")]
public List<SearchFilter>? Search { get; set; }
[GraphQLName("Sorted")]
public List<Sort>? Sorted { get; set; }
[GraphQLName("Where")]
[GraphQLType(typeof(AnyType))]
public List<WhereFilter>? Where { get; set; }
[GraphQLName("Group")]
public List<string>? Group { get; set; }
[GraphQLName("antiForgery")]
public string? antiForgery { get; set; }
[GraphQLName("Table")]
public string? Table { get; set; }
[GraphQLName("IdMapping")]
public string? IdMapping { get; set; }
[GraphQLName("Select")]
public List<string>? Select { get; set; }
[GraphQLName("Expand")]
public List<string>? Expand { get; set; }
[GraphQLName("Distinct")]
public List<string>? Distinct { get; set; }
[GraphQLName("ServerSideGroup")]
public bool? ServerSideGroup { get; set; }
[GraphQLName("LazyLoad")]
public bool? LazyLoad { get; set; }
[GraphQLName("LazyExpandAllGroup")]
public bool? LazyExpandAllGroup { get; set; }
}
public class Aggregate
{
[GraphQLName("Field")]
public string Field { get; set; }
[GraphQLName("Type")]
public string Type { get; set; }
}
public class SearchFilter
{
[GraphQLName("Fields")]
public List<string> Fields { get; set; }
[GraphQLName("Key")]
public string Key { get; set; }
[GraphQLName("Operator")]
public string Operator { get; set; }
[GraphQLName("IgnoreCase")]
public bool IgnoreCase { get; set; }
}
public class Sort
{
[GraphQLName("Name")]
public string Name { get; set; }
[GraphQLName("Direction")]
public string Direction { get; set; }
[GraphQLName("Comparer")]
[GraphQLType(typeof(AnyType))]
public object Comparer { get; set; }
}
public class WhereFilter
{
[GraphQLName("Field")]
public string? Field { get; set; }
[GraphQLName("IgnoreCase")]
public bool? IgnoreCase { get; set; }
[GraphQLName("IgnoreAccent")]
public bool? IgnoreAccent { get; set; }
[GraphQLName("IsComplex")]
public bool? IsComplex { get; set; }
[GraphQLName("Operator")]
public string? Operator { get; set; }
[GraphQLName("Condition")]
public string? Condition { get; set; }
[GraphQLName("value")]
[GraphQLType(typeof(AnyType))]
public object? value { get; set; }
[GraphQLName("predicates")]
public List<WhereFilter>? predicates { get; set; }
}Note
You can get the entire code in the github sample.
SQL Server data binding(SQL Client)
The following examples demonstrate how to consume data from SQL Server using Microsoft SqlClient and bound it to Blazor DataGrid. You can achieve this requirement by using Custom Adaptor.
Before the implementation, add required NuGet like Microsoft.Data.SqlClient and Syncfusion.Blazor in your application. In the following sample, Custom Adaptor can be created as a Component. In custom adaptor Read method, you can get grid action details like paging, filtering, sorting information etc., using DataManagerRequest.
Based on the DataManagerRequest, you can form SQL query string (to perform paging) and execute the SQL query and retrieve the data from database using SqlDataAdapter. The Fill method of the DataAdapter is used to populate a DataSet with the results of the SelectCommand of the DataAdapter, then convert the DataSet into List and return Result and Count pair object in Read method to bind the data to Grid.
@using Syncfusion.Blazor.Grids;
@using Syncfusion.Blazor.Data;
@using Syncfusion.Blazor;
<SfGrid TValue="Order" AllowPaging="true">
<SfDataManager Adaptor="Adaptors.CustomAdaptor">
<CustomAdaptorComponent></CustomAdaptorComponent>
</SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsIdentity="true" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120">
</GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
SfGrid<Order> Grid { get; set; }
public static List<Order> Orders { get; set; }
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
}
}@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Data;
@using Newtonsoft.Json
@using static EFGrid.Pages.Index;
@using Microsoft.Data.SqlClient;
@using System.Data;
@using System.IO;
@using Microsoft.AspNetCore.Hosting;
@inject IHostingEnvironment _env
@inherits DataAdaptor<Order>
<CascadingValue Value="@this">
@ChildContent
</CascadingValue>
@code {
[Parameter]
[JsonIgnore]
public RenderFragment ChildContent { get; set; }
public static DataSet CreateCommand(string queryString, string connectionString)
{
using (SqlConnection connection = new SqlConnection(
connectionString))
{
SqlDataAdapter adapter = new SqlDataAdapter(queryString, connection);
DataSet dt = new DataSet();
try
{
connection.Open();
adapter.Fill(dt);// using sqlDataAdapter we process the query string and fill the data into dataset
}
catch (SqlException se)
{
Console.WriteLine(se.ToString());
}
finally
{
connection.Close();
}
return dt;
}
}
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
string appdata = _env.ContentRootPath;
string path = Path.Combine(appdata, "App_Data\\NORTHWND.MDF");
string str = $"Data Source=(LocalDB)\\MSSQLLocalDB;AttachDbFilename='{path}';Integrated Security=True;Connect Timeout=30";
// based on the skip and take count from DataManagerRequest here we formed SQL query string
string qs = "SELECT OrderID, CustomerID FROM dbo.Orders ORDER BY OrderID OFFSET " + dm.Skip + " ROWS FETCH NEXT " + dm.Take + " ROWS ONLY;";
DataSet data = CreateCommand(qs, str);
Orders = data.Tables[0].AsEnumerable().Select(r => new Order
{
OrderID = r.Field<int>("OrderID"),
CustomerID = r.Field<string>("CustomerID")
}).ToList(); // here we convert dataset into list
IEnumerable<Order> DataSource = Orders;
SqlConnection conn = new SqlConnection(str);
conn.Open();
SqlCommand comm = new SqlCommand("SELECT COUNT(*) FROM dbo.Orders", conn);
Int32 count = (Int32)comm.ExecuteScalar();
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}NOTE
- In this sample, paging action is handled for Blazor grid. Based on your needs, you can extend the given logic for other operations.
* For performing data manipulation, you can override available methods such as Insert, Update and Remove of the Custom Adaptor.
Entity Framework
You need to follow the below steps to consume data from the Entity Framework in the datagrid component.
Create DBContext class
The first step is to create a DBContext class called OrderContext to connect to a Microsoft SQL Server database.
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using EFGrid.Shared.Models;
namespace EFGrid.Shared.DataAccess
{
public class OrderContext : DbContext
{
public virtual DbSet<Order> Orders { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
if (!optionsBuilder.IsConfigured)
{
optionsBuilder.UseSqlServer(@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename='F:\blazor\EFGrid - CRUD - P6\EFGrid.Shared\App_Data\NORTHWND.MDF';Integrated Security=True;Connect Timeout=30");
}
}
}
}Create data access layer to perform data operation
Now, you need to create a class named OrderDataAccessLayer, which act as data access layer for retrieving the records and also insert, update and delete the records from the database table.
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using EFGrid.Shared.Models;
namespace EFGrid.Shared.DataAccess
{
public class OrderDataAccessLayer
{
OrderContext db = new OrderContext();
public DbSet<Order> GetAllOrders()
{
try
{
return db.Orders;
}
catch
{
throw;
}
}
}
}Creating Web API Controller
A Web API Controller has to be created which allows datagrid directly to consume data from the Entity Framework.
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using EFGrid.Shared.DataAccess;
using EFGrid.Shared.Models;
namespace WebApplication1.Server.Controllers
{
[Route("api/[controller]")]
[ApiController]
public class DefaultController : ControllerBase
{
OrderDataAccessLayer db = new OrderDataAccessLayer();
[HttpGet]
public object Get()
{
IQueryable<Order> data = db.GetAllOrders().AsQueryable();
var count = data.Count();
var queryString = Request.Query;
if (queryString.Keys.Contains("$inlinecount"))
{
StringValues Skip;
StringValues Take;
int skip = (queryString.TryGetValue("$skip", out Skip)) ? Convert.ToInt32(Skip[0]) : 0;
int top = (queryString.TryGetValue("$top", out Take)) ? Convert.ToInt32(Take[0]) : data.Count();
return new { Items = data.Skip(skip).Take(top), Count = count };
}
else
{
return data;
}
}
}
}Configure datagrid component using Web API adaptor
Now, you can configure the datagrid using the ‘SfDataManager’ to interact with the created Web API and consume the data appropriately. To interact with web api, you need to use WebApiAdaptor.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowPaging="true" >
<SfDataManager Url="api/Default" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" IsIdentity="true" TextAlign="@Syncfusion.Blazor.Grids.TextAlign.Right" Width="90"></GridColumn>
<GridColumn Field="CustomerID" HeaderText="Customer ID" Width="90"></GridColumn>
<GridColumn Field="EmployeeID" HeaderText="Employee ID" Width="90"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public class Order {
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
}To perform datagrid CRUD operation using Entity Framework. You can refer here.
N>You can find the fully working sample here.
HTTP client
It is possible to call web api from the Blazor WebAssembly(client-side) app. This can be used for sending HTTP requests to fetch data from web api and bind them in the DataGrid’s data source. The requests are sent using HttpClient service.
This can be achieved by initially injecting the HttpClient instance in the app.
@using System.Net.Http
@inject HttpClient HttpAfter that the data to be fetched is defined in the api controller of the Blazor WebAssembly app.
[Route("api/[controller]")]
[ApiController]
public class EmployeeController : ControllerBase
{
List<Employee> employee = new List<Employee>();
[HttpGet]
public object Get()
{
employee.Add(new Employee { EmployeeID = 1, FirstName = "Andrew", LastName = "Fuller", Title = "Branch Manager" });
employee.Add(new Employee { EmployeeID = 2, FirstName = "Nancy", LastName = "Leverling", Title = "Product Manager" });
employee.Add(new Employee { EmployeeID = 3, FirstName = "Anne", LastName = "Dodsworth", Title = "Team Lead" });
employee.Add(new Employee { EmployeeID = 4, FirstName = "Laura", LastName = "Callahan", Title = "Product Manager" });
employee.Add(new Employee { EmployeeID = 5, FirstName = "Michael", LastName = "Suyama", Title = "Team Lead" });
employee.Add(new Employee { EmployeeID = 6, FirstName = "Robert", LastName = "King", Title = "Developer" });
employee.Add(new Employee { EmployeeID = 7, FirstName = "Janet", LastName = "Peacock", Title = "Developer" });
employee.Add(new Employee { EmployeeID = 8, FirstName = "Steven", LastName = "Buchanan", Title = "Developer" });
employee.Add(new Employee { EmployeeID = 9, FirstName = "Margaret", LastName = "Davolio", Title = "Developer" });
return employee;
}
}
public class Employee
{
public int? EmployeeID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Title { get; set; }
}Then using the GetJsonAsync method request is sent to the api controller for fetching data which is bounded to the DataGrid’s data source
@using Syncfusion.Blazor.Grids
@inject HttpClient Http
<SfGrid DataSource="@Empdata" AllowPaging="true">
<GridPageSettings PageSize="7"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Employee.EmployeeID) HeaderText="Employee ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Employee.FirstName) HeaderText="First Name" Width="120"></GridColumn>
<GridColumn Field=@nameof(Employee.LastName) HeaderText="Last Name" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Employee.Title) HeaderText="Title" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public List<Employee> Empdata { get; set; }
protected override async Task OnInitializedAsync()
{
Empdata = await Http.GetJsonAsync<List<Employee>>("api/Employee");
}
public class Employee
{
public int? EmployeeID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Title { get; set; }
}
}NOTE
The above steps are processed in the Blazor WebAssembly app which has the pre-configured
HttpClientservice. For Blazor server apps, web api calls are created using IHttpClientFactory. More information on making requests usingIHttpClientFactoryis available in this link.
Observable collection
This ObservableCollection(dynamic data collection) provides notifications when items added, removed and moved. The implement INotifyCollectionChanged notifies when dynamic changes of add,remove, move and clear the collection. The implement INotifyPropertyChanged notifies when property value has changed in client side.
Here, Order class implements the interface of INotifyPropertyChanged and it raises the event when CustomerID property value was changed.
@using Syncfusion.Blazor.Grids
@using System.Collections.ObjectModel
@using System.ComponentModel
<button id="add" @onclick="AddRecords">Add Data</button>
<button id="del" @onclick="DelRecords">Delete Data</button>
<button id="update" @onclick="UpdateRecords">Update Data</button>
<SfGrid DataSource="@GridData" AllowReordering="true">
<GridColumns>
<GridColumn Field=@nameof(OrdersDetailsObserveData.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" HeaderTextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(OrdersDetailsObserveData.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(OrdersDetailsObserveData.Freight) HeaderText="Freight" EditType="EditType.NumericEdit" Format="C2" Width="140" TextAlign="@TextAlign.Right" HeaderTextAlign="@TextAlign.Right"></GridColumn>
<GridColumn Field=@nameof(OrdersDetailsObserveData.OrderDate) HeaderText="Order Date" EditType="EditType.DatePickerEdit" Format="d" Type="ColumnType.Date" Width="160"></GridColumn>
<GridColumn Field=@nameof(OrdersDetailsObserveData.ShipCountry) HeaderText="Ship Country" EditType="EditType.DropDownEdit" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public ObservableCollection<OrdersDetailsObserveData> GridData { get; set; }
public int Count = 32341;
protected override void OnInitialized()
{
GridData = OrdersDetailsObserveData.GetRecords();
}
public void AddRecords()
{
GridData.Add(new OrdersDetailsObserveData(Count++, "ALFKI", 4343, 2.3 * 43, false, new DateTime(1991, 05, 15), "Berlin", "Simons bistro", "Denmark", new DateTime(1996, 7, 16), "Kirchgasse 6"));
}
public void DelRecords()
{
GridData.Remove(GridData.First());
}
public void UpdateRecords()
{
var a = GridData.First();
a.CustomerID = "Update";
}
public class OrdersDetailsObserveData : INotifyPropertyChanged
{
public OrdersDetailsObserveData()
{
}
public OrdersDetailsObserveData(int OrderID, string CustomerId, int EmployeeId, double Freight, bool Verified, DateTime OrderDate, string ShipCity, string ShipName, string ShipCountry, DateTime ShippedDate, string ShipAddress)
{
this.OrderID = OrderID;
this.CustomerID = CustomerId;
this.EmployeeID = EmployeeId;
this.Freight = Freight;
this.ShipCity = ShipCity;
this.Verified = Verified;
this.OrderDate = OrderDate;
this.ShipName = ShipName;
this.ShipCountry = ShipCountry;
this.ShippedDate = ShippedDate;
this.ShipAddress = ShipAddress;
}
public static ObservableCollection<OrdersDetailsObserveData> GetRecords()
{
ObservableCollection<OrdersDetailsObserveData> order = new ObservableCollection<OrdersDetailsObserveData>();
int code = 10000;
for (int i = 1; i < 2; i++)
{
order.Add(new OrdersDetailsObserveData(code + 1, "ALFKI", i + 0, 2.3 * i, false, new DateTime(1991, 05, 15), "Berlin", "Simons bistro", "Denmark", new DateTime(1996, 7, 16), "Kirchgasse 6"));
order.Add(new OrdersDetailsObserveData(code + 2, "ANATR", i + 2, 3.3 * i, true, new DateTime(1990, 04, 04), "Madrid", "Queen Cozinha", "Brazil", new DateTime(1996, 9, 11), "Avda. Azteca 123"));
order.Add(new OrdersDetailsObserveData(code + 3, "ANTON", i + 1, 4.3 * i, true, new DateTime(1957, 11, 30), "Cholchester", "Frankenversand", "Germany", new DateTime(1996, 10, 7), "Carrera 52 con Ave. Bol�var #65-98 Llano Largo"));
order.Add(new OrdersDetailsObserveData(code + 4, "BLONP", i + 3, 5.3 * i, false, new DateTime(1930, 10, 22), "Marseille", "Ernst Handel", "Austria", new DateTime(1996, 12, 30), "Magazinweg 7"));
order.Add(new OrdersDetailsObserveData(code + 5, "BOLID", i + 4, 6.3 * i, true, new DateTime(1953, 02, 18), "Tsawassen", "Hanari Carnes", "Switzerland", new DateTime(1997, 12, 3), "1029 - 12th Ave. S."));
code += 5;
}
return order;
}
public int OrderID { get; set; }
public string CustomerID
{
get { return customerID; }
set
{
customerID = value;
NotifyPropertyChanged("CustomerID");
}
}
public string customerID { get; set; }
public int? EmployeeID { get; set; }
public double? Freight { get; set; }
public string ShipCity { get; set; }
public bool Verified { get; set; }
public DateTime? OrderDate { get; set; }
public event PropertyChangedEventHandler PropertyChanged;
public string ShipName { get; set; }
public string ShipCountry { get; set; }
public DateTime ShippedDate { get; set; }
public string ShipAddress { get; set; }
private void NotifyPropertyChanged(String propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}The following screenshot represents the DataGrid with Observable Collection.
NOTE
While using an Observable collection, the added, removed, and changed records are reflected in the UI. But while updating the Observable collection using external actions like timers, events, and other notifications, you need to call the StateHasChanged method to reflect the changes in the UI.
Troubleshoot: DataGrid renders without data even though server returns with correct data
In ASP.NET Core, by default the JSON results are returned in camelCase format. So datagrid field names are also changed in camelCase.
To avoid this problem, you need to add DefaultContractResolver in Startup.cs file.
public void ConfigureServices(IServiceCollection services)
{
services.AddRazorPages();
services.AddServerSideBlazor().AddCircuitOptions();
services.AddSingleton<WeatherForecastService>();
services.AddMvc().AddNewtonsoftJson(options =>
{
options.SerializerSettings.ContractResolver = new DefaultContractResolver();
});
}Handling exceptions
Exceptions occurred during grid actions can be handled without stopping application. These error messages or exception details can be acquired using the OnActionFailure event.
The argument passed to the OnActionFailure event contains the error details returned from the server.
NOTE
We recommend you to bind OnActionFailure event during your application development phase, this helps you to find any exceptions. You can pass these exception details to our support team to get solution as early as possible.
The following sample code demonstrates notifying user when server-side exception has occurred during data operation,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<span class="error">@ErrorDetails</span>
<SfGrid TValue="Order" AllowPaging="true">
<GridEvents TValue="Order" OnActionFailure="@ActionFailure"></GridEvents>
<GridPageSettings PageSize="10"></GridPageSettings>
<SfDataManager Url="https://some.com/invalidUrl" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
</GridColumns>
</SfGrid>
<style>
.error {
color: red;
}
</style>
@code{
public string ErrorDetails = "";
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
public void ActionFailure(FailureEventArgs args)
{
this.ErrorDetails = "Server exception: 404 Not found";
StateHasChanged();
}
}Perform data operation in WebAPI service
While using the WebAPI adaptor type in the SfDataManager component, queries will be generated for data operations to be sent to the server side as QueryString, and based on these QueryString values, actions(filtering, sorting, paging, etc.) will be performed on the server side.
Requests sent to the server can be retrieved using “Request.Query”, and these values can be differentiated as below.
| Keys | Explanation |
|---|---|
| $skip, $top | This contains query for performing paging operation in server side. |
| $filter | This contains query for performing filtering operation in server side. |
| $search | This contains query for performing searching operation in server side. |
| $orderby | This contains query for performing sorting operation in server side. |
Using the above QueryString keys, you can get the corresponding values and perform the required actions. In the following sample, simple filtering, sorting, and paging operations are demonstrated.
@using Grid_WebAPI.Data
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" AllowFiltering="true" Toolbar="@(new List<string> {"Add","Edit","Delete","Update","Cancel","Search" })" AllowSorting="true" AllowPaging="true">
<SfDataManager Url="api/Default" Adaptor="Adaptors.WebApiAdaptor"></SfDataManager>
<GridEditSettings AllowAdding="true" AllowDeleting="true" AllowEditing="true"></GridEditSettings>
<GridColumns>
<GridColumn Field="EmployeeID" HeaderText="ID" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="OrderID" HeaderText="Order ID" IsPrimaryKey="true" TextAlign="TextAlign.Right" Width="120"></GridColumn>
<GridColumn Field="CustomerID" HeaderText="Customer Name" Width="150"></GridColumn>
</GridColumns>
</SfGrid>public class DefaultController : ControllerBase
{
public OrderDataAccessLayer OrderService = new OrderDataAccessLayer();
// GET: api/Default
[HttpGet]
public async Task<object> Get(int? code)
{
try
{
Microsoft.AspNetCore.Http.IQueryCollection queryString = Request.Query;
if (queryString == null)
return null;
IQueryable<Order> dataSource = OrderService.GetAllOrders();
int countAll = dataSource.Count();
StringValues sSkip, sTake, sFilter, sSort;
// Performing Filtering operation at server side.
string filter = (queryString.TryGetValue("$filter", out sFilter)) ? sFilter[0] : null; //filter query
List<DynamicLinqExpression.Filter> listFilter = ParsingFilterFormula.PrepareFilter(filter);
if (listFilter.Count() > 0)
{
Expression<Func<Order, bool>> deleg = DynamicLinqExpression.ExpressionBuilder.GetExpressionFilter<Order>(listFilter);
dataSource = dataSource.Where(deleg);
}
// Performing Sorting operation at server side.
string sort = (queryString.TryGetValue("$orderby", out sSort)) ? sSort[0] : null; //sort query
if (sort != null)
{
string s = DynamicLinqExpression.GetSortString(sort);
if (s == null)
return null;
else if (s.Length > 0)
{
dataSource = dataSource.OrderBy(s);
}
}
int countFiltered = dataSource.Count();
// Performing Paging operation at server side.
int skip = (queryString.TryGetValue("$skip", out sSkip)) ? Convert.ToInt32(sSkip[0]) : 0;
int top = (queryString.TryGetValue("$top", out sTake)) ? Convert.ToInt32(sTake[0]) : countAll;
dataSource = dataSource.Skip(skip).Take(top);
if (queryString.Keys.Contains("$inlinecount"))
return new { Items = dataSource, Count = countFiltered };
else
return dataSource;
}
catch (Exception ex)
{
return null;
}
}
}NOTE
Similarly, we suggest you handle the same scenarios for complex queries.
NOTE
NOTE
ASP.NET Core (Blazor) Web API with batch handling is not yet supported by ASP.NET Core v3+. Hence, it is not feasible for us to support batch mode CRUD operations until ASP.NET Core provides the support for the batch handler. Refer here for more details.