Getting Started with Blazor Dropdown List in Blazor WASM App
29 Jun 202610 minutes to read
This guide briefly explains how to include Blazor Dropdown List component in a Blazor WebAssembly App using Visual Studio, Visual Studio Code, and the .NET CLI. Ensure a valid Syncfusion license is registered in the application and choose a theme (Bootstrap, Fluent, Material, or Tailwind) as part of setup.
Create a new Blazor WebAssembly (Standalone) App
Create a Blazor WebAssembly App using Visual Studio via Microsoft Templates or the Blazor Extension.
Run the following command to create a new Blazor WebAssembly App.
dotnet new blazorwasm -o BlazorApp
cd BlazorAppAlternatively, create a Blazor WebAssembly App using Visual Studio Code via Microsoft Templates or the Blazor Extension, or the C# Dev Kit extension.
Run the following command to create a new Blazor WebAssembly App.
dotnet new blazorwasm -o BlazorApp
cd BlazorAppInstall the required Blazor packages
Install the Syncfusion.Blazor.DropDowns and Syncfusion.Blazor.Themes NuGet packages. All Syncfusion Blazor packages are available on nuget.org. See the NuGet packages topic for details.
- Go to Tools → NuGet Package Manager → Manage NuGet Packages for Solution.
- Search the required NuGet packages (
Syncfusion.Blazor.DropDownsandSyncfusion.Blazor.Themes) and install them.
Alternatively, you can install the same packages using the Package Manager Console with the following commands.
Install-Package Syncfusion.Blazor.DropDowns -Version 34.1.29
Install-Package Syncfusion.Blazor.Themes -Version 34.1.29Open the terminal and run the following commands.
dotnet add package Syncfusion.Blazor.DropDowns -v 34.1.29
dotnet add package Syncfusion.Blazor.Themes -v 34.1.29Open the command prompt and run the following commands.
dotnet add package Syncfusion.Blazor.DropDowns -v 34.1.29
dotnet add package Syncfusion.Blazor.Themes -v 34.1.29Add import namespaces
After the packages are installed, open the ~/_Imports.razor file and import the Syncfusion.Blazor and Syncfusion.Blazor.DropDowns namespaces.
@using Syncfusion.Blazor
@using Syncfusion.Blazor.DropDownsRegister the Blazor service
Open the Program.cs file in Blazor WebAssembly App and register the Blazor service.
....
using Syncfusion.Blazor;
....
builder.Services.AddSyncfusionBlazor();
....Add stylesheet and script resources
The theme stylesheet and script can be accessed from NuGet through Static Web Assets. Include the stylesheet and script references in the ~wwwroot/index.html file.
...
<link href="_content/Syncfusion.Blazor.Themes/fluent2.css" rel="stylesheet" />
...
<script src="_content/Syncfusion.Blazor.Core/scripts/syncfusion-blazor.min.js" type="text/javascript"></script>Add Blazor Dropdown List component
Open a Razor file located in the ~/Pages/*.razor (for example, Home.razor) and add the Blazor Dropdown List component inside the razor file.
@using Syncfusion.Blazor.DropDowns
<SfDropDownList TValue="string" TItem="string" Placeholder="Select a game"></SfDropDownList>Run the application
Press Ctrl+F5 (Windows) or ⌘+F5 (macOS) to launch the application. The Blazor Dropdown List component will render in your default web browser.
Open the terminal and run the following command.
dotnet runOpen the command prompt and run the following command.
dotnet run
NOTE
Binding data source
After initialization, populate the DropDownList with data using the DataSource property.
@using Syncfusion.Blazor.DropDowns
<SfDropDownList TValue="string" TItem="Games" Placeholder="Select a game" DataSource="@LocalData">
<DropDownListFieldSettings Value="ID" Text="Text"></DropDownListFieldSettings>
</SfDropDownList>
@code
{
public class Games
{
public string ID { get; set; }
public string Text { get; set; }
}
List<Games> LocalData = new List<Games> {
new Games() { ID= "Game1", Text= "American Football" },
new Games() { ID= "Game2", Text= "Badminton" },
new Games() { ID= "Game3", Text= "Basketball" },
new Games() { ID= "Game4", Text= "Cricket" },
new Games() { ID= "Game5", Text= "Football" },
new Games() { ID= "Game6", Text= "Golf" },
new Games() { ID= "Game7", Text= "Hockey" },
new Games() { ID= "Game8", Text= "Rugby"},
new Games() { ID= "Game9", Text= "Snooker" },
new Games() { ID= "Game10", Text= "Tennis"},
};
}
Configure the popup list
By default, the popup list width automatically adjusts to the Dropdown List input width, and the popup list height is 350px. Customize the height and width using the PopupHeight and PopupWidth properties.
@using Syncfusion.Blazor.DropDowns
<SfDropDownList TValue="string" TItem="Games" PopupHeight="350px" PopupWidth="350px" Placeholder="Select a game" DataSource="@LocalData">
<DropDownListFieldSettings Value="ID" Text="Text"></DropDownListFieldSettings>
</SfDropDownList>
@code
{
public class Games
{
public string ID { get; set; }
public string Text { get; set; }
}
List<Games> LocalData = new List<Games> {
new Games() { ID= "Game1", Text= "American Football" },
new Games() { ID= "Game2", Text= "Badminton" },
new Games() { ID= "Game3", Text= "Basketball" },
new Games() { ID= "Game4", Text= "Cricket" },
new Games() { ID= "Game5", Text= "Football" },
new Games() { ID= "Game6", Text= "Golf" },
new Games() { ID= "Game7", Text= "Hockey" },
new Games() { ID= "Game8", Text= "Rugby"},
new Games() { ID= "Game9", Text= "Snooker" },
new Games() { ID= "Game10", Text= "Tennis"},
};
}
Get selected value
Get the selected value of the DropDownList component in the ValueChange event using the ChangeEventArgs.Value property.
@using Syncfusion.Blazor.DropDowns
<SfDropDownList TValue="string" TItem="Games" Placeholder="Select a game" DataSource="@LocalData">
<DropDownListFieldSettings Value="Text" Text="Text"></DropDownListFieldSettings>
<DropDownListEvents TValue="string" TItem="Games" ValueChange="OnValueChange"></DropDownListEvents>
</SfDropDownList>
@code {
public class Games
{
public string ID { get; set; }
public string Text { get; set; }
}
List<Games> LocalData = new List<Games> {
new Games() { ID= "Game1", Text= "American Football" },
new Games() { ID= "Game2", Text= "Badminton" },
new Games() { ID= "Game3", Text= "Basketball" },
new Games() { ID= "Game4", Text= "Cricket" },
new Games() { ID= "Game5", Text= "Football" },
new Games() { ID= "Game6", Text= "Golf" },
new Games() { ID= "Game7", Text= "Hockey" },
new Games() { ID= "Game8", Text= "Rugby"},
new Games() { ID= "Game9", Text= "Snooker" },
new Games() { ID= "Game10", Text= "Tennis"},
};
public void OnValueChange(ChangeEventArgs<string, Games> args)
{
Console.WriteLine($"The DropDownList Value is: {args.Value}");
}
}Get the complete data object for the selected value in the ValueChange event using the ChangeEventArgs.ItemData property.
@using Syncfusion.Blazor.DropDowns
<SfDropDownList TValue="string" TItem="Games" Placeholder="Select a game" DataSource="@LocalData">
<DropDownListFieldSettings Value="ID" Text="Text"></DropDownListFieldSettings>
<DropDownListEvents TValue="string" TItem="Games" ValueChange="OnValueChange"></DropDownListEvents>
</SfDropDownList>
@code {
public class Games
{
public string ID { get; set; }
public string Text { get; set; }
}
List<Games> LocalData = new List<Games> {
new Games() { ID= "Game1", Text= "American Football" },
new Games() { ID= "Game2", Text= "Badminton" },
new Games() { ID= "Game3", Text= "Basketball" },
new Games() { ID= "Game4", Text= "Cricket" },
new Games() { ID= "Game5", Text= "Football" },
new Games() { ID= "Game6", Text= "Golf" },
new Games() { ID= "Game7", Text= "Hockey" },
new Games() { ID= "Game8", Text= "Rugby"},
new Games() { ID= "Game9", Text= "Snooker" },
new Games() { ID= "Game10", Text= "Tennis"},
};
public void OnValueChange(ChangeEventArgs<string, Games> args)
{
Console.WriteLine($"Selected - ID: {args.ItemData.ID}, Game: {args.ItemData.Text}");
}
}