Bind data from RESTful web services to Syncfusion Blazor components and perform CRUD operations

4 Aug 202117 minutes to read

In this topic, we are going to learn how to retrieve data from RESTful web services, bind data to a Grid component, and perform CRUD operations. Here, we have fetched data from the ODataV4 service using ODataV4Adaptor of SfDataManger.

It is recommended to choose the suitable adaptor based on the RESTful service which you are using to bind data for the Syncfusion Blazor component. Please refer to the following documentation to know about the available Adaptors of SfDataManager.

Prerequisite software

The following software are needed

  • Visual Studio 2019 v16.8.0 Preview 3.0 or later.
  • .NET SDK 5.0 RC2 or later.

Create the database

Open Visual Studio 2019 Preview, select View -> SQL Server Object Explorer. Right-click on the Databases folder to create a new Database and name it as OrdersDetails.

Add new database
Adding database name and location

Right-click on the Tables folder of the created database and click Add New Table.

Add table

Use the following query to add a new table named Orders.

Create Table Orders(
 OrderID BigInt Identity(1,1) Primary Key Not Null,
 CustomerID Varchar(100) Not Null,
 Freight int Null,
 OrderDate datetime null
)

Now, the Orders table design will look like below. Click on the Update button.

Database table design

Now, click on Update Database.

Update database

Create OData service project

Open Visual Studio 2019 and create an empty ASP.NET Core Web Application and name it as ODataServiceProject. After creating the application, install Microsoft.AspNetCore.OData package by running the following command in the Package Manager Console.

  • Install-Package Microsoft.AspNetCore.OData -Version 7.3.0: This package contains everything you need to create OData v4.0 endpoints using ASP.NET Core MVC and to support OData query syntax for your web APIs.

Generate DbContext and model class from the database

Now, we are going to scaffold DbContext and model classes from the existing OrdersDetails database. To perform scaffolding and work with the SQL Server database in our application, we need to install the following NuGet packages.

Run the following commands in the Package Manager Console.

  • Install-Package Microsoft.EntityFrameworkCore.Tools -Version 3.0.0: This package creates database context and model classes from the database.
  • Install-Package Microsoft.EntityFrameworkCore.SqlServer -Version 3.0.0: The database provider that allows Entity Framework Core to work with SQL Server.

Once the above packages are installed, we can scaffold DbContext and Model classes. Run the following command in the Package Manager Console.


Scaffold-DbContext “Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=OrdersDetails;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False” Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models

The above scaffolding command contains the following details for creating DbContext and model classes for the existing database and its tables.

  • Connection string: Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=OrdersDetails;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False
  • Data provider: Microsoft.EntityFrameworkCore.SqlServer
  • Output directory: -OutputDir Models

After running the above command, the OrdersDetailsContext.cs and Orders.cs files will be created under the ODataServiceProject.Models folder as follows.

Models folder

We can see that OrdersDetailsContext.cs file contains the connection string details in the OnConfiguring method.

Remove connection string from context file

It is not recommended to have a connection string with sensitive information in the OrdersDetailsContext.cs file, so we are moving the connection string to the appsettings.json file.

Add connection string in appsettings

Now, the DbContext must be configured using connection string and registered as scoped service using the AddDbContext method in Startup.cs.

Register service

Creating ODataV4 Service

The application is now configured to connect with the OrdersDetails database using Entity Framework. Now, it’s time to consume data from the OrdersDetails database. To do so, we need an OData controller to serve data from the DbContext to the Blazor application.

To create OData controller, right-click Controller folder in ODataServiceProject and select Add -> New Item -> API controller with read/write actions. We are naming this controller as OrdersController as it returns Orders table records.

Now, replace the controller with the following code which contains code to handle CRUD operations in the Orders table.

using Microsoft.AspNet.OData;
using System.Threading.Tasks;
using ODataServiceProject.Models;
using Microsoft.AspNetCore.Mvc;

// For more information on enabling Web API for empty projects, visit https://go.microsoft.com/fwlink/?LinkID=397860

namespace ODataServiceProject.Controllers
{
    [Route("api/[controller]")]
    public class OrdersController : ODataController
    {
        private OrdersDetailsContext _db;
        public OrdersController(OrdersDetailsContext context)
        {
            _db = context;
        }
        [HttpGet]
        [EnableQuery]
        public IActionResult Get()
        {
            return Ok(_db.Orders);
        }
        [EnableQuery]
        public async Task<IActionResult> Post([FromBody] Orders book)
        {
            _db.Orders.Add(book);
            _db.SaveChanges();
            return Created(book);
        }
        [EnableQuery]
        public async Task<IActionResult> Patch([FromODataUri] long key, [FromBody] Delta<Orders> book)
        {
            var entity = await _db.Orders.FindAsync(key);
            book.Patch(entity);
            await _db.SaveChangesAsync();
            return Updated(entity);
        }
        [EnableQuery]
        public long Delete([FromODataUri] long key)
        {
            var deleterow = _db.Orders.Find(key);
            _db.Orders.Remove(deleterow);
            _db.SaveChanges();
            return key;
        }
    }
}

Add the following line in the launchSettings.json file.

{
  "iisSettings": {
    "windowsAuthentication": false,
    "anonymousAuthentication": true,
    "iisExpress": {
      "applicationUrl": "http://localhost:59323",
      "sslPort": 44392
    }
  },
  "profiles": {
    "IIS Express": {
      "commandName": "IISExpress",
      "launchBrowser": true,
      "launchUrl": "odata/orders",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    },
    "ODataServiceProject": {
      "commandName": "Project",
      "dotnetRunMessages": "true",
      "launchBrowser": true,
      "applicationUrl": "https://localhost:5001;http://localhost:5000",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    }
  }
}

Open Startup.cs file and configure by referring to the following codes.

namespace ODataServiceProject
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }
        public IConfiguration Configuration { get; }
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<OrdersDetailsContext>(option => option.UseSqlServer(Configuration.GetConnectionString("OrdersDetailsDatabase")));
            services.AddOData();
            services.AddMvc(option => option.EnableEndpointRouting = false).SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
        }
        private static IEdmModel GetEdmModel()
        {
            ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
            var books = builder.EntitySet<Orders>("Orders");
            FunctionConfiguration myFirstFunction = books.EntityType.Collection.Function("MyFirstFunction");
            myFirstFunction.ReturnsCollectionFromEntitySet<Orders>("Orders");
            return builder.GetEdmModel();
        }
        // This method gets called at the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
                routes.Count().Filter().OrderBy().Expand().Select().MaxTop(null);
                routes.MapODataServiceRoute(
                 "odata",
                 "odata",
                 model: GetEdmModel()
               );
            });
        }
    }
}

Create Blazor Server Application

Open Visual Studio 2019 and follow the steps in the below documentation to create the Blazor Server Application.

Getting Started

Add Syncfusion Blazor DataGrid package

To add Syncfusion components into the project, right-click Dependencies and select Manage NuGet Packages.

Manage Nuget Packages

Now, in the Browse tab, search and install the Syncfusion.Blazor.Grid NuGet package.

Add Syncfusion package

For this demo, we have used Syncfusion.Blazor(19.1.0.66) NuGet package. We have released a new Syncfusion.Blazor NuGet package with new enhancement in our every-week release and main release. So, you can check and update to the latest versions by using this link.

Open _Import.razor file and add the following namespaces which are required to use Syncfusion Blazor components in this application.

@using Syncfusion.Blazor
@using Syncfusion.Blazor.Grids
@using Syncfusion.Blazor.Data
@using ODataServiceProject.Models

Open Startup.cs file and register the Syncfusion service in the ConfigureServices method as follows.

public void ConfigureServices(IServiceCollection services)
{
    services.AddRazorPages();
    services.AddServerSideBlazor();
    services.AddSingleton<WeatherForecastService>();
    services.AddSyncfusionBlazor();
}

Themes provide life to components. Syncfusion Blazor has different themes. They are:

  • Bootstrap4
  • Material
  • Office 365
  • Bootstrap
  • High Contrast

In this demo application, the Bootstrap4 theme will be used. To add the theme, open Pages/_Host.cshtml file and add the following CSS reference code.

<link href="_content/Syncfusion.Blazor.Themes/fabric.css" rel="stylesheet" />

Add Syncfusion Blazor DataGrid component to an application

In previous steps, we have successfully configured the Syncfusion Blazor package in the application. Now, we can add the grid component to the Index.razor page.

<SfGrid TValue="Orders"></SfGrid>

Binding data to Blazor DataGrid component using ODataV4Adaptor

To consume data from the OData Controller, we need to add the SfDataManager with ODataV4Adaptor. Please refer to the following documentation for more details on ODataV4Adaptor.

ODataV4Adaptor

<SfGrid TValue="Orders">
    <SfDataManager Url="https://localhost:44392/odata/orders" Adaptor="Adaptors.ODataV4Adaptor"></SfDataManager>
</SfGrid>

In the above code example, we have used our localhost address from our application. Instead of localhost, you can give the exact URL of your OData service.

Grid columns can be defined by using the GridColumn component. We are going to create columns using the following code.

<SfGrid TValue="Orders">
    <SfDataManager Url="https://localhost:44392/odata/orders" Adaptor="Adaptors.ODataV4Adaptor"></SfDataManager>
    <GridColumns>
        <GridColumn Field=@nameof(Orders.OrderId) HeaderText="Order ID" IsPrimaryKey="true" Visible="false" TextAlign="TextAlign.Right" Width="120"></GridColumn>
        <GridColumn Field=@nameof(Orders.CustomerId) HeaderText="Customer Name" Width="150"></GridColumn>
        <GridColumn Field=@nameof(Orders.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
        <GridColumn Field=@nameof(Orders.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
    </GridColumns>
</SfGrid>

When you run the application, the Get() method will be called in your OData controller.

[Route("api/[controller]")]
public class OrdersController : ODataController
{
    private OrdersDetailsContext _db;
    public OrdersController(OrdersDetailsContext context)
    {
        _db = context;
    }
    [HttpGet]
    [EnableQuery]
    public IActionResult Get()
    {
        return Ok(_db.Orders);
    }
    ...
}

Handling CRUD operations with our Syncfusion Blazor DataGrid component

We can enable editing in the grid component using the GridEditSettings component. Grid provides various modes of editing options such as Inline/Normal, Dialog, and Batch editing.

Here, we are using Inline edit mode and used Toolbar property to show toolbar items for editing.
We have added the DataGrid Editing and Toolbar code with previous Grid model.

<SfGrid TValue="Orders" Toolbar="@(new List<string>() { "Add", "Edit", "Delete", "Cancel", "Update" })">
    <SfDataManager Url="https://localhost:44392/odata/orders" Adaptor="Adaptors.ODataV4Adaptor"></SfDataManager>
    <GridEditSettings AllowAdding="true" AllowDeleting="true" AllowEditing="true" Mode="EditMode.Normal"></GridEditSettings>
    <GridColumns>
        <GridColumn Field=@nameof(Orders.OrderId) HeaderText="Order ID" IsPrimaryKey="true" Visible="false" TextAlign="TextAlign.Right" Width="120"></GridColumn>
        <GridColumn Field=@nameof(Orders.CustomerId) HeaderText="Customer Name" Width="150"></GridColumn>
        <GridColumn Field=@nameof(Orders.OrderDate) HeaderText=" Order Date" Format="d" Type="ColumnType.Date" TextAlign="TextAlign.Right" Width="130"></GridColumn>
        <GridColumn Field=@nameof(Orders.Freight) HeaderText="Freight" Format="C2" TextAlign="TextAlign.Right" Width="120"></GridColumn>
    </GridColumns>
</SfGrid>

Normal editing is the default edit mode for the DataGrid component. Set the IsPrimaryKey property of Column as true for a particular column, whose value is a unique value for editing purposes.

Insert a row

To insert a new row, click the Add toolbar button. The new record edit form will look like below.

Insert Operation

Clicking the Update toolbar button will insert the record in the Orders table by calling the below POST method of the OData controller.

[EnableQuery]
public async Task<IActionResult> Post([FromBody] Orders book)
{
    _db.Orders.Add(book);
    _db.SaveChanges();
    return Created(book);
}

Insert Operation

Update a row

To edit a row, select any row and click the Edit toolbar button. The edit form will look like below. Edit the Customer Name column.

Update Operation

Clicking the Update toolbar button will update the record in the Orders table by calling the below PATCH method of the OData controller.

[EnableQuery]
public async Task<IActionResult> Patch([FromODataUri] long key, [FromBody] Delta<Orders> book)
{
    var entity = await _db.Orders.FindAsync(key);
    book.Patch(entity);
    await _db.SaveChangesAsync();
    return Updated(entity);
}

The resultant grid will look like below.

Update Operation

Delete a row

To delete a row, select any row and click the Delete toolbar button. Deleting operation will send a DELETE request to the OData controller with the selected record`s primary key value to remove the corresponding record from the Orders table.

[EnableQuery]
public long Delete([FromODataUri] long key)
{
    var deleterow = _db.Orders.Find(key);
    _db.Orders.Remove(deleterow);
    _db.SaveChanges();
    return key;
}

Please find the sample from this Github location.