Getting Started with ASP.NET Core DropDownList Control

23 Jul 20263 minutes to read

This section briefly explains how to include the ASP.NET Core DropDownList control in your ASP.NET Core application using Visual Studio.

Create an ASP.NET Core Web App with Razor pages

Create an ASP.NET Core Web App using Visual Studio via Microsoft Templates or the ASP.NET Core Extension. For detailed instructions, refer to the ASP.NET Core Web App Getting Started documentation.

Install the required ASP.NET Core packages

To add ASP.NET Core DropDownList control in the app, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search for and install the Syncfusion.AspNetCore.DropDowns and Syncfusion.AspNetCore.Themes packages. All Syncfusion ASP.NET Core packages are available in nuget.org. See the NuGet packages topic for details.

Alternatively, you can install the same package using the Package Manager Console with the following command.

Install-Package Syncfusion.AspNetCore.DropDowns -Version 34.1.29
Install-Package Syncfusion.AspNetCore.Themes -Version 34.1.29

Add the ASP.NET Core Tag Helpers

After the packages are installed, open the ~/Pages/_ViewImports.cshtml file and import the Syncfusion.AspNetCore.Base and Syncfusion.AspNetCore.DropDowns Tag Helpers.

@addTagHelper *, Syncfusion.AspNetCore.Base
@addTagHelper *, Syncfusion.AspNetCore.DropDowns

Add stylesheet and script resources

The theme stylesheet and script can be referenced from CDN. Include the stylesheet and script references inside the <head> of ~/Pages/Shared/_Layout.cshtml.

<head>
    ...
    @* ASP.NET Core controls styles *@
    <link rel="stylesheet" href="_content/Syncfusion.AspNetCore.Themes/styles/fluent2.css" />
    @* ASP.NET Core controls scripts *@
    <script src="_content/Syncfusion.AspNetCore.DropDowns/scripts/sf-drop-down-list.min.js"></script>
</head>

Register the Script Manager

Open the ~/Pages/Shared/_Layout.cshtml file and register the script manager <ejs-scripts> at the end of the <body> element as follows.

<body>
    ...
    @*  ASP.NET Core Script Manager *@
    <ejs-scripts></ejs-scripts>
</body>

Add ASP.NET Core DropDownList control

Add the ASP.NET Core DropDownList control in the ~/Pages/Index.cshtml file.

@{
    var data = new string[] { "Badminton", "Basketball", "Cricket", "Football", "Golf", "Gymnastics", "Hockey", "Tennis" };
}

<ejs-dropdownlist id="games" dataSource="data"> </ejs-dropdownlist>

Run the application

Press Ctrl+F5 (Windows) or ⌘+F5 (macOS) to launch the application. The ASP.NET Core DropDownList will render in your default web browser.

ASP.NET Core DropDownList Control

Binding data source

After initialization, populate the DropDownList with data using the dataSource property. Here, an array of string values is passed to the DropDownList component.

@{
    ...
    var data = new string[] { "Badminton", "Basketball", "Cricket", "Football", "Golf", "Gymnastics", "Hockey", "Tennis" };
}

<ejs-dropdownlist id="games" dataSource="data" placeholder="Select a game" popupHeight="220px">
</ejs-dropdownlist>

Configure the popup list

By default, the width of the popup list automatically adjusts according to the DropDownList input element’s width, and the height of the popup list has 300px.

The height and width of the popup list can also be customized using the popupHeight and popupWidth properties respectively.

@{
    ...
    var data = new string[] { "Badminton", "Basketball", "Cricket", "Football", "Golf", "Gymnastics", "Hockey", "Tennis" };
}

<ejs-dropdownlist id="games" dataSource="data" popupWidth="300px" placeholder="Select a game" popupHeight="220px">
</ejs-dropdownlist>

NOTE

View Sample in GitHub.

See also