Getting Started with ASP.NET MVC DropDownList Control

4 May 20224 minutes to read

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

Prerequisites

System requirements for ASP.NET MVC controls

Create ASP.NET MVC application with HTML helper

Install ASP.NET MVC package in the application

Syncfusion ASP.NET MVC controls are available in nuget.org. Refer to NuGet packages topic to learn more about installing NuGet packages in various OS environments. To add ASP.NET MVC controls in the application, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search for Syncfusion.EJ2.MVC5 and then install it.

The Syncfusion.EJ2.MVC5 NuGet package has dependencies, Newtonsoft.Json for JSON serialization and Syncfusion.Licensing for validating Syncfusion license key.

If you create ASP.NET MVC application with MVC4 package, search for Syncfusion.EJ2.MVC4 and then install it.

Add namespace

Add Syncfusion.EJ2 namespace reference in Web.config under Views folder.

<namespaces>
    <add namespace="Syncfusion.EJ2"/>
</namespaces>

Add style sheet

Checkout the Themes topic to learn different ways (CDN, NPM package, and CRG) to refer styles in ASP.NET MVC application, and to have the expected appearance for Syncfusion ASP.NET MVC controls. Here, the theme is referred using CDN inside the <head> of ~/Views/Shared/_Layout.cshtml file as follows,

<head>
    ...
    <!-- Syncfusion ASP.NET MVC controls styles -->
    <link rel="stylesheet" href="https://cdn.syncfusion.com/ej2/20.3.56/fluent.css" />
</head>

Add script reference

In this getting started walk-through, the required scripts are referred using CDN inside the <head> of ~/Views/Shared/_Layout.cshtml file as follows,

<head>
    ...
    <!-- Syncfusion ASP.NET MVC controls scripts -->
    <script src="https://cdn.syncfusion.com/ej2/20.3.56/dist/ej2.min.js"></script>
</head>

Register Syncfusion Script Manager

Open ~/Views/Shared/_Layout.cshtml page and register the script manager EJS().ScriptManager() at the end of <body> in the ASP.NET MVC application as follows.

<body>
...
    <!-- Syncfusion ASP.NET MVC Script Manager -->
    @Html.EJS().ScriptManager()
</body>

Add ASP.NET MVC DropDownList control

Now, add the Syncfusion ASP.NET MVC DropDownList control in ~/Views/Home/Index.cshtml page.

@model List<string>

@Html.EJS().DropDownList("games").DataSource((IEnumerable<object>)Model).Render()
public ActionResult Index()
{
    List<string> data = new List<string>() { "Badminton", "Basketball", "Cricket", "Football", "Golf", "Gymnastics", "Hockey", "Tennis" };
    return View(data);
}

Press Ctrl+F5 (Windows) or +F5 (macOS) to run the app. Then, the Syncfusion ASP.NET MVC DropDownList control will be rendered in the default web browser.

ASP.NET MVC 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 control.

The following example illustrates the output in your browser.

@model List<string>

@Html.EJS().DropDownList("games").Placeholder("Select a game").DataSource((IEnumerable<object>)Model).Render()
public ActionResult Index()
{
    List<string> data = new List<string>() { "Badminton", "Basketball", "Cricket", "Football", "Golf", "Gymnastics", "Hockey", "Tennis" };
    return View(data);
}

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.

In the following sample, popup list’s width and height are configured.

@model List<string>

@Html.EJS().DropDownList("games").Placeholder("Select a game").PopupHeight("200px").PopupWidth("300px").DataSource((IEnumerable<object>)Model).Render()
public ActionResult Index()
{
    List<string> data = new List<string>() { "Badminton", "Basketball", "Cricket", "Football", "Golf", "Gymnastics", "Hockey", "Tennis" };
    return View(data);
}

View Sample in GitHub.

See also