Getting Started with Blazor TreeGrid Component

24 May 202215 minutes to read

This section briefly explains about how to include Blazor TreeGrid component in your Blazor Server App and Blazor WebAssembly App using Visual Studio.

Prerequisites

Create a new Blazor App in Visual Studio

You can create Blazor Server App or Blazor WebAssembly App using Visual Studio in one of the following ways,

Install Syncfusion Blazor TreeGrid NuGet in the App

Syncfusion Blazor components are available in nuget.org. To use Syncfusion Blazor components in the application, add reference to the corresponding NuGet. Refer to NuGet packages topic for available NuGet packages list with component details.

To add Blazor TreeGrid component in the app, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search for Syncfusion.Blazor.TreeGrid and then install it.

Register Syncfusion Blazor Service

Open ~/_Imports.razor file and import the Syncfusion.Blazor namespace.

@using Syncfusion.Blazor

Now, register the Syncfusion Blazor Service in the Blazor Server App or Blazor WebAssembly App. Here, Syncfusion Blazor Service is registered by setting IgnoreScriptIsolation property as true to load the scripts externally in the next steps.

From 2022 Vol1 (20.1) version - The default value of IgnoreScriptIsolation is changed as true, so, you don’t have to set IgnoreScriptIsolation property explicitly to refer scripts externally.

Blazor Server App

  • For .NET 6 app, open the ~/Program.cs file and register the Syncfusion Blazor Service.

  • For .NET 5 and .NET 3.X app, open the ~/Startup.cs file and register the Syncfusion Blazor Service.

using Microsoft.AspNetCore.Components;
using Microsoft.AspNetCore.Components.Web;
using Syncfusion.Blazor;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddRazorPages();
builder.Services.AddServerSideBlazor();
builder.Services.AddSyncfusionBlazor(options => { options.IgnoreScriptIsolation = true; });

var app = builder.Build();
....
using Syncfusion.Blazor;

namespace BlazorApplication
{
    public class Startup
    {
        ...
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddRazorPages();
            services.AddServerSideBlazor();
            services.AddSyncfusionBlazor(options => { options.IgnoreScriptIsolation = true; });
        }
        ...
    }
}

Blazor WebAssembly App

Open ~/Program.cs file and register the Syncfusion Blazor Service in the client web app.

using Microsoft.AspNetCore.Components.Web;
using Microsoft.AspNetCore.Components.WebAssembly.Hosting;
using Syncfusion.Blazor;

var builder = WebAssemblyHostBuilder.CreateDefault(args);
builder.RootComponents.Add<App>("#app");
builder.RootComponents.Add<HeadOutlet>("head::after");

builder.Services.AddScoped(serviceProvider => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });

builder.Services.AddSyncfusionBlazor(options => { options.IgnoreScriptIsolation = true; });
await builder.Build().RunAsync();
....
using Syncfusion.Blazor;

namespace WebApplication1
{
    public class Program
    {
        public static async Task Main(string[] args)
        {
            ....
            builder.Services.AddSyncfusionBlazor(options => { options.IgnoreScriptIsolation = true; });
            await builder.Build().RunAsync();
        }
    }
}

Add Style Sheet

Checkout the Blazor Themes topic to learn different ways (Static Web Assets, CDN and CRG) to refer themes in Blazor application, and to have the expected appearance for Syncfusion Blazor components. Here, the theme is referred using Static Web Assets. Refer to Enable static web assets usage topic to use static assets in your project.

To add theme to the app, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search for Syncfusion.Blazor.Themes and then install it. Then, the theme style sheet from NuGet can be referred as follows,

Blazor Server App

  • For .NET 6 app, add the Syncfusion bootstrap5 theme in the <head> of the ~/Pages/_Layout.cshtml file.

  • For .NET 5 and .NET 3.X app, add the Syncfusion bootstrap5 theme in the <head> of the ~/Pages/_Host.cshtml file.

<head>
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
</head>
<head>
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
</head>

Blazor WebAssembly App

For Blazor WebAssembly App, Refer the theme style sheet from NuGet in the <head> of wwwroot/index.html file in the client web app.

<head>
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
</head>

Add Script Reference

Checkout Adding Script Reference topic to learn different ways to add script reference in Blazor Application. In this getting started walk-through, the required scripts are referred using Static Web Assets externally inside the <head> as follows. Refer to Enable static web assets usage topic to use static assets in your project.

Blazor Server App

  • For .NET 6 app, Refer script in the <head> of the ~/Pages/_Layout.cshtml file.

  • For .NET 5 and .NET 3.X app, Refer script in the <head> of the ~/Pages/_Host.cshtml file.

<head>
    ....
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>
    <!--Use below script reference if you are using Syncfusion.Blazor Single NuGet-->
    <!--<script  src="_content/Syncfusion.Blazor/scripts/syncfusion-blazor.min.js"  type="text/javascript"></script>-->
</head>
<head>
    ....
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>
    <!--Use below script reference if you are using Syncfusion.Blazor Single NuGet-->
    <!--<script  src="_content/Syncfusion.Blazor/scripts/syncfusion-blazor.min.js"  type="text/javascript"></script>-->
</head>

Blazor WebAssembly App

For Blazor WebAssembly App, Refer script in the <head> of the ~/index.html file.

<head>
    ....
    <link href="_content/Syncfusion.Blazor.Themes/bootstrap5.css" rel="stylesheet" />
    <script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>
    <!--Use below script reference if you are using Syncfusion.Blazor Single NuGet-->
    <!--<script  src="_content/Syncfusion.Blazor/scripts/syncfusion-blazor.min.js"  type="text/javascript"></script>-->
</head>

Syncfusion recommends to reference scripts using Static Web Assets, CDN and CRG by disabling JavaScript isolation for better loading performance of the Blazor application.

Add Blazor TreeGrid component

  • Open ~/_Imports.razor file or any other page under the ~/Pages folder where the component is to be added and import the Syncfusion.Blazor.TreeGrid namespace.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.TreeGrid
  • Now, add the Syncfusion Blazor TreeGrid component in razor file. Here, the TreeGrid component is added in the ~/Pages/Index.razor file under the ~/Pages folder.
<SfTreeGrid DataSource="@TreeData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1">
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="5" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Center"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="30" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Center"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

@code
{
    public class BusinessObject
    {
        public int TaskId { get; set; }
        public string TaskName { get; set; }
        public int? ParentId { get; set; }
    }

    public List<BusinessObject> TreeData = new List<BusinessObject>();

    protected override void OnInitialized()
    {
        TreeData.Add(new BusinessObject() { TaskId = 1, TaskName = "Parent Task 1", ParentId = null });
        TreeData.Add(new BusinessObject() { TaskId = 2, TaskName = "Child task 1", ParentId = 1 });
        TreeData.Add(new BusinessObject() { TaskId = 3, TaskName = "Child Task 2", ParentId = 1, });
        TreeData.Add(new BusinessObject() { TaskId = 4, TaskName = "Parent Task 2", ParentId = null });
        TreeData.Add(new BusinessObject() { TaskId = 5, TaskName = "Child Task 5", ParentId = 4 });
        TreeData.Add(new BusinessObject() { TaskId = 6, TaskName = "Child Task 6", ParentId = 5 });
    }
}
  • Press Ctrl+F5 (Windows) or +F5 (macOS) to run the application. Then, the Syncfusion Blazor TreeGrid component will be rendered in the default web browser.

Blazor TreeGrid

Defining columns

The Tree Grid has an option to define columns using the TreeGridColumns directive. In the TreeGridColumn directive there are properties to customize columns.

Let’s check the properties used here:

  • Field to map with a property name in datasource is been added.
  • HeaderText to change the title of columns is been added.
  • TextAlign to change the alignment of columns is been used. By default, columns will be left aligned. To change columns to right align, define TextAlign as Right.
<SfTreeGrid DataSource="@TreeData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1">
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="160"></TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Progress" HeaderText="Progress" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Priority" HeaderText="Priority" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

@code{

    public class BusinessObject
    {
        public int TaskId { get; set; }
        public string TaskName { get; set; }
        public int Duration { get; set; }
        public int Progress { get; set; }
        public string Priority { get; set; }
        public int? ParentId { get; set; }
    }

    public List<BusinessObject> TreeData = new List<BusinessObject>();

    protected override void OnInitialized()
    {
        TreeData.Add(new BusinessObject() { TaskId = 1, TaskName = "Parent Task 1", Duration = 10, Progress = 70, ParentId = null, Priority = "High" });
        TreeData.Add(new BusinessObject() { TaskId = 2, TaskName = "Child task 1", Duration = 4, Progress = 80, ParentId = 1, Priority = "Normal" });
        TreeData.Add(new BusinessObject() { TaskId = 3, TaskName = "Child Task 2", Duration = 5, Progress = 65, ParentId = 1, Priority = "Critical" });
        TreeData.Add(new BusinessObject() { TaskId = 4, TaskName = "Parent Task 2", Duration = 6, Progress = 77, ParentId = null, Priority = "Low" });
        TreeData.Add(new BusinessObject() { TaskId = 5, TaskName = "Child Task 5", Duration = 9, Progress = 25, ParentId = 4, Priority = "Normal" });
        TreeData.Add(new BusinessObject() { TaskId = 6, TaskName = "Child Task 6", Duration = 9, Progress = 7, ParentId = 5, Priority = "Normal" });
        TreeData.Add(new BusinessObject() { TaskId = 7, TaskName = "Parent Task 3", Duration = 4, Progress = 45, ParentId = null, Priority = "High" });
        TreeData.Add(new BusinessObject() { TaskId = 8, TaskName = "Child Task 7", Duration = 3, Progress = 38, ParentId = 7, Priority = "Critical" });
        TreeData.Add(new BusinessObject() { TaskId = 9, TaskName = "Child Task 8", Duration = 7, Progress = 70, ParentId = 7, Priority = "Low" });
    }
}

In the above code example, the Self-Referential data binding is represented in which the IdMapping and ParentIdMapping properties denotes the hierarchy relationship; whereas in Hierarchical data binding ChildMapping denotes the hierarchy relationship.

Enable paging

The paging feature enables users to view the tree grid record in a paged view. It can be enabled by setting the AllowPaging property to true. The pager can be customized using the PageSettings property.

In root-level paging mode, paging is based on the root-level rows only, i.e., it ignores the child row count and it can be enabled by using the PageSettings.PageSizeMode property.

<SfTreeGrid DataSource="@TreeData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1" AllowPaging="true">
    <TreeGridPageSettings PageSizeMode="PageSizeMode.Root" PageSize="2"></TreeGridPageSettings>
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="160"></TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Progress" HeaderText="Progress" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Priority" HeaderText="Priority" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

Enable sorting

The sorting feature enables to order the records. It can be enabled by setting the AllowSorting property to true.

<SfTreeGrid DataSource="@TreeData" IdMapping="TaskId" ParentIdMapping="ParentId" TreeColumnIndex="1" AllowPaging="true" AllowSorting="true">
    <TreeGridPageSettings PageSizeMode="PageSizeMode.Root" PageSize="2"></TreeGridPageSettings>
    <TreeGridColumns>
        <TreeGridColumn Field="TaskId" HeaderText="Task ID" Width="80" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="TaskName" HeaderText="Task Name" Width="160"></TreeGridColumn>
        <TreeGridColumn Field="Duration" HeaderText="Duration" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Progress" HeaderText="Progress" Width="100" TextAlign="Syncfusion.Blazor.Grids.TextAlign.Right"></TreeGridColumn>
        <TreeGridColumn Field="Priority" HeaderText="Priority" Width="80"></TreeGridColumn>
    </TreeGridColumns>
</SfTreeGrid>

Blazor TreeGrid

View Sample in GitHub.

See also