Custom Binding in Blazor DataGrid Component
27 Sep 202324 minutes to read
The SfDataManager has custom adaptor support which allows you to perform manual operations on the data. This can be utilized for implementing custom data binding and editing operations in the DataGrid component.
For implementing custom data binding in DataGrid, the DataAdaptor class is used. This abstract class acts as a base class for the custom adaptor.
The DataAdaptor abstract class has both synchronous and asynchronous method signatures which can be overridden in the custom adaptor. Following are the method signatures present in this class,
public abstract class DataAdaptor
{
/// <summary>
/// Performs data Read operation synchronously.
/// </summary>
public virtual object Read(DataManagerRequest dataManagerRequest, string key = null)
/// <summary>
/// Performs data Read operation asynchronously.
/// </summary>
public virtual Task<object> ReadAsync(DataManagerRequest dataManagerRequest, string key = null)
/// <summary>
/// Performs Insert operation synchronously.
/// </summary>
public virtual object Insert(DataManager dataManager, object data, string key)
/// <summary>
/// Performs Insert operation asynchronously.
/// </summary>
public virtual Task<object> InsertAsync(DataManager dataManager, object data, string key)
/// <summary>
/// Performs Remove operation synchronously.
/// </summary>
public virtual object Remove(DataManager dataManager, object data, string keyField, string key)
/// <summary>
/// Performs Remove operation asynchronously.
/// </summary>
public virtual Task<object> RemoveAsync(DataManager dataManager, object data, string keyField, string key)
/// <summary>
/// Performs Update operation synchronously.
/// </summary>
public virtual object Update (DataManager dataManager, object data, string keyField, string key)
/// <summary>
/// Performs Update operation asynchronously.
/// </summary>
public virtual Task<object> UpdateAsync(DataManager dataManager, object data, string keyField, string key)
/// <summary>
/// Performs Batch CRUD operations synchronously.
/// </summary>
public virtual object BatchUpdate(DataManager dataManager, object changedRecords, object addedRecords, object deletedRecords, string keyField, string key, int? dropIndex)
/// <summary>
/// Performs Batch CRUD operations asynchronously.
/// </summary>
public virtual Task<object> BatchUpdateAsync(DataManager dataManager, object changedRecords, object addedRecords, object deletedRecords, string keyField, string key, int? dropIndex)
}Data binding
The custom data binding can be performed in the DataGrid component by providing the custom adaptor class and overriding the Read or ReadAsync method of the DataAdaptor abstract class.
The following sample code demonstrates implementing custom data binding using custom adaptor,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" ID="Grid" AllowSorting="true" AllowFiltering="true" AllowPaging="true">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
}
public class Order
{
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
// 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)
{
IEnumerable<Order> DataSource = Orders;
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DataOperations.PerformSearching(DataSource, dm.Search);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
DataResult DataObject = new DataResult();
if (dm.Aggregates != null) // Aggregation
{
DataObject.Result = DataSource;
DataObject.Count = count;
DataObject.Aggregates = DataUtil.PerformAggregation(DataSource, dm.Aggregates);
return dm.RequiresCounts ? DataObject : (object)DataSource;
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}NOTE
If the DataManagerRequest.RequiresCounts value is true, then the Read/ReadAsync return value must be of DataResult with properties Result whose value is a collection of records and Count whose value is the total number of records. If the DataManagerRequest.RequiresCounts is false, then simply send the collection of records.
The following image shows the custom bound data displayed in the DataGrid component,
NOTE
If the Read/ReadAsync method is not overridden in the custom adaptor, then it will be handled by the default read handler.
Inject service into Custom Adaptor
If you want to inject some of your service into Custom Adaptor and use the service, then you can achieve your requirement by using below way.
Initially, you need to add CustomAdaptor class as AddScoped in Program.cs file.
builder.Services.AddSingleton<OrderDataAccessLayer>();
builder.Services.AddScoped<CustomAdaptor>();
builder.Services.AddScoped<ServiceClass>();The following sample code demonstrates injecting service into Custom Adaptor,
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
@using Syncfusion.Blazor
<SfGrid TValue="Order" ID="Grid" AllowSorting="true" AllowFiltering="true" AllowPaging="true">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public class CustomAdaptor : DataAdaptor
{
//Here, you can inject your service
public OrderDataAccessLayer context { get; set; };
public CustomAdaptor(OrderDataAccessLayer _context)
{
context = _context;
}
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
IEnumerable<Order> DataSource = context.GetAllOrders();
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DataOperations.PerformSearching(DataSource, dm.Search);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}Custom adaptor as Component
Custom Adaptor can be created as a component when DataAdaptor is extended from OwningComponentBase. You can create Custom Adaptor from any of the two versions of the class, DataAdaptor and DataAdaptor<T>.
Ensure to register your service in Program.cs file.
builder.Services.AddScoped<Order>();The following sample code demonstrates creating Custom Adaptor as a component,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" ID="Grid" AllowSorting="true" AllowFiltering="true" AllowPaging="true">
<SfDataManager Adaptor="Adaptors.CustomAdaptor">
<CustomAdaptorComponent></CustomAdaptorComponent>
</SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
public class Order
{
public List<Order> GetAllRecords()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
return Orders;
}
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
}The following sample code demonstrates DataAdaptor extended from OwningComponentBase<T>. This provides a single service of type T. You can access this service by using the Service property.
[CustomAdaptorComponent.razor]
@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Data;
@using Newtonsoft.Json
@using static BlazorApp1.Pages.Index;
@inherits DataAdaptor<Order>
<CascadingValue Value="@this">
@ChildContent
</CascadingValue>
@code {
[Parameter]
[JsonIgnore]
public RenderFragment ChildContent { get; set; }
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
IEnumerable<Order> DataSource = (IEnumerable<Order>)Service.GetAllRecords();
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DataOperations.PerformSearching(DataSource, dm.Search);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}The following sample code demonstrates DataAdaptor extended from OwningComponentBase. This provides the possibility to request multiple services.
[CustomAdaptorComponent.razor]
@using Syncfusion.Blazor;
@using Syncfusion.Blazor.Data;
@using static BlazorApp1.Pages.Index
@using Newtonsoft.Json
@inherits DataAdaptor
<CascadingValue Value="@this">
@ChildContent
</CascadingValue>
@code {
[Parameter]
[JsonIgnore]
public RenderFragment ChildContent { get; set; }
Order orderdata;
public override object Read(DataManagerRequest dm, string key = null)
{
orderdata = (Order)ScopedServices.GetService(typeof(Order));
IEnumerable<Order> DataSource = (IEnumerable<Order>)orderdata.GetAllRecords().Take(10);
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DataOperations.PerformSearching(DataSource, dm.Search);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}Handling Editing in Custom Adaptor
The CRUD operations for the custom bound data in the DataGrid component can be implemented by overriding the following CRUD methods of the DataAdaptor abstract class,
- Insert/InsertAsync
- Remove/RemoveAsync
- Update/UpdateAsync
- BatchUpdate/BatchUpdateAsync
NOTE
While using batch editing in DataGrid, use BatchUpdate/BatchUpdateAsync method to handle the corresponding CRUD operation.
The following sample code demonstrates implementing CRUD operations for the custom bound data,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" ID="Grid" AllowSorting="true" AllowFiltering="true" AllowPaging="true" Toolbar="@(new List<string>() { "Add", "Delete", "Update", "Cancel" })">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridEditSettings AllowEditing="true" AllowDeleting="true" AllowAdding="true" Mode="@EditMode.Normal"></GridEditSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
}
public class Order
{
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
// 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)
{
IEnumerable<Order> DataSource = Orders;
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DataOperations.PerformSearching(DataSource, dm.Search);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(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)
{
Orders.Insert(0, value as Order);
return value;
}
// Performs Remove operation
public override object Remove(DataManager dm, object value, string keyField, string key)
{
Orders.Remove(Orders.Where(or => or.OrderID == int.Parse(value.ToString())).FirstOrDefault());
return value;
}
// Performs Update operation
public override object Update(DataManager dm, object value, string keyField, string key)
{
var data = Orders.Where(or => or.OrderID == (value as Order).OrderID).FirstOrDefault();
if (data != null)
{
data.OrderID = (value as Order).OrderID;
data.CustomerID = (value as Order).CustomerID;
data.Freight = (value as Order).Freight;
}
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)
{
foreach (var rec in (IEnumerable<Order>)Changed)
{
Order val = Orders.Where(or => or.OrderID == rec.OrderID).FirstOrDefault();
val.OrderID = rec.OrderID;
val.CustomerID = rec.CustomerID;
val.Freight = rec.Freight;
}
}
if (Added != null)
{
foreach (var rec in (IEnumerable<Order>)Added)
{
Orders.Add(rec);
}
}
if (Deleted != null)
{
foreach (var rec in (IEnumerable<Order>)Deleted)
{
Orders.Remove(Orders.Where(or => or.OrderID == rec.OrderID).FirstOrDefault());
}
}
return Orders;
}
}
}The following GIF displays the CRUD operations performed on the custom bound data displayed in the DataGrid component,
NOTE
You can refer to the Blazor DataGrid feature tour page for its groundbreaking feature representations. You can also explore Blazor DataGrid example to understand how to present and manipulate data.
Handling Aggregates in Custom Adaptor
When using Custom Adaptor, the aggregates must be handled in the Read/ReadAsync method of Custom adaptor.
The following sample code demonstrates implementing the aggregates for the custom bound data,
@using Syncfusion.Blazor.Grids
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor
<SfGrid TValue="Order" AllowPaging="true">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridAggregates>
<GridAggregate>
<GridAggregateColumns>
<GridAggregateColumn Field=@nameof(Order.Freight) Type="AggregateType.Sum" Format="C2">
<FooterTemplate>
@{
var aggregate = (context as AggregateTemplateContext);
<div>
<p>Sum: @aggregate.Sum</p>
</div>
}
</FooterTemplate>
</GridAggregateColumn>
</GridAggregateColumns>
</GridAggregate>
<GridAggregate>
<GridAggregateColumns>
<GridAggregateColumn Field=@nameof(Order.Freight) Type="AggregateType.Average" Format="C2">
<FooterTemplate>
@{
var aggregate = (context as AggregateTemplateContext);
<div>
<p>Average: @aggregate.Average</p>
</div>
}
</FooterTemplate>
</GridAggregateColumn>
</GridAggregateColumns>
</GridAggregate>
</GridAggregates>
<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.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 static List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
OrderDate = DateTime.Now.AddDays(-x),
}).ToList();
}
public class Order
{
public int? OrderID { get; set; }
public string CustomerID { get; set; }
public DateTime? OrderDate { get; set; }
public double? Freight { get; set; }
}
public class CustomAdaptor : DataAdaptor
{
// Performs data Read operation
public override object Read(DataManagerRequest dm, string key = null)
{
IEnumerable<Order> DataSource = Orders;
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
DataResult DataObject = new DataResult();
if (dm.Aggregates != null) // Aggregation
{
DataObject.Result = DataSource;
DataObject.Count = count;
DataObject.Aggregates = DataUtil.PerformAggregation(DataSource, dm.Aggregates);
return dm.RequiresCounts ? DataObject : (object)DataSource;
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}Handling Grouping in Custom Adaptor
When using Custom Adaptor, the grouping operation has to be handled in the Read/ReadAsync method of Custom adaptor.
The following sample code demonstrates implementing the grouping operation for the custom bounded data,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
@using System.Collections
<SfGrid TValue="Order" ID="Grid" AllowPaging="true" AllowGrouping="true">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
}
public class Order
{
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
// 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)
{
IEnumerable<Order> DataSource = Orders;
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
DataResult DataObject = new DataResult();
if (dm.Group != null)
{
IEnumerable ResultData = DataSource.ToList();
// Grouping
foreach (var group in dm.Group)
{
ResultData = DataUtil.Group<Order>(ResultData, group, dm.Aggregates, 0, dm.GroupByFormatter);
}
DataObject.Result = ResultData;
DataObject.Count = count;
return dm.RequiresCounts ? DataObject : (object)ResultData;
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}Handling Filtering in Custom Adaptor
When using a custom adaptor, the filtering operation has to be handled by overriding the Read/ReadAsync method of the DataAdaptor abstract class. In the DataManagerRequest class, you can get the grid action details as shown in the below image.
Based on these grid action details, a custom data source can be filtered using the built-in PerformFiltering method of the DataOperations class.
NOTE
Also, you can use your own method to do the filtering operation and bind the resultant data to the grid.
The following sample code demonstrates implementing the filtering operation for the custom bounded data,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
@using System.Collections
<SfGrid TValue="Order" ID="Grid" AllowFiltering="true" AllowPaging="true">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
}
public class Order
{
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
// 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)
{
IEnumerable<Order> DataSource = Orders;
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}NOTE
Handling Sorting in Custom Adaptor
When using a custom adaptor, the sorting operation has to be handled by overriding the Read/ReadAsync method of the DataAdaptor abstract class. In the DataManagerRequest class, you can get the grid action details as shown in the below image.
Based on these grid action details, a custom data source can be sorted using the built-in PerformSorting method of the DataOperations class.
NOTE
Also, you can use your own method to do the sorting operation and bind the resultant data to the grid.
The following sample code demonstrates implementing the sorting operation for the custom bounded data,
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
@using System.Collections
<SfGrid TValue="Order" ID="Grid" AllowSorting="true" AllowPaging="true">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
}
public class Order
{
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
// 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)
{
IEnumerable<Order> DataSource = Orders;
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}NOTE
How to pass additional parameters to custom adaptor
To send an additional 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 to the custom adaptor using the Query property of Grid.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.Data
@using Syncfusion.Blazor.Grids
<SfGrid TValue="Order" ID="Grid" AllowSorting="true" AllowFiltering="true" AllowPaging="true" Query="@Query">
<SfDataManager AdaptorInstance="@typeof(CustomAdaptor)" Adaptor="Adaptors.CustomAdaptor"></SfDataManager>
<GridPageSettings PageSize="8"></GridPageSettings>
<GridColumns>
<GridColumn Field=@nameof(Order.OrderID) HeaderText="Order ID" IsPrimaryKey="true" TextAlign="@TextAlign.Center" Width="140"></GridColumn>
<GridColumn Field=@nameof(Order.CustomerID) HeaderText="Customer Name" Width="150"></GridColumn>
<GridColumn Field=@nameof(Order.Freight) HeaderText="Freight" Format="C2" Width="150"></GridColumn>
</GridColumns>
</SfGrid>
@code{
public static List<Order> Orders { get; set; }
public Query Query = new Query().AddParams("Code", 10);
protected override void OnInitialized()
{
Orders = Enumerable.Range(1, 75).Select(x => new Order()
{
OrderID = 1000 + x,
CustomerID = (new string[] { "ALFKI", "ANANTR", "ANTON", "BLONP", "BOLID" })[new Random().Next(5)],
Freight = 2.1 * x,
}).ToList();
}
public class Order
{
public int OrderID { get; set; }
public string CustomerID { get; set; }
public double Freight { get; set; }
}
// 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)
{
IEnumerable<Order> DataSource = Orders;
if (dm.Params != null && dm.Params.Count > 0)
{
var val = dm.Params;
}
if (dm.Search != null && dm.Search.Count > 0)
{
// Searching
DataSource = DataOperations.PerformSearching(DataSource, dm.Search);
}
if (dm.Sorted != null && dm.Sorted.Count > 0)
{
// Sorting
DataSource = DataOperations.PerformSorting(DataSource, dm.Sorted);
}
if (dm.Where != null && dm.Where.Count > 0)
{
// Filtering
DataSource = DataOperations.PerformFiltering(DataSource, dm.Where, dm.Where[0].Operator);
}
int count = DataSource.Cast<Order>().Count();
if (dm.Skip != 0)
{
//Paging
DataSource = DataOperations.PerformSkip(DataSource, dm.Skip);
}
if (dm.Take != 0)
{
DataSource = DataOperations.PerformTake(DataSource, dm.Take);
}
DataResult DataObject = new DataResult();
if (dm.Aggregates != null) // Aggregation
{
DataObject.Result = DataSource;
DataObject.Count = count;
DataObject.Aggregates = DataUtil.PerformAggregation(DataSource, dm.Aggregates);
return dm.RequiresCounts ? DataObject : (object)DataSource;
}
return dm.RequiresCounts ? new DataResult() { Result = DataSource, Count = count } : (object)DataSource;
}
}
}