Getting Started with the RadioGroup

This tutorial explains how to set up a basic Telerik UI for ASP.NET Core RadioGroup component and highlights the major steps in the configuration of the component.

You will initialize a RadioGroup component with a set of items. Then, you will use the events of the UI component. Finally, you can run the sample code in Telerik REPL and continue exploring the components.

Prerequisites

To successfully complete the tutorial, you need a project that is already configured to use the Telerik UI for ASP.NET Core components:

• You can use the Telerik REPL playground and skip installing the components on your system and configuring a project.

• You can prepare a Visual Studio project by following either of these guides:

  • Creating a new pre-configured project for the Telerik UI for ASP.NET Core components from a project template.

  • Manually configuring an existing project as described in the First Steps on Windows or First Steps on Mac articles.

1. Prepare the CSHTML File

The first step is to add the required directives at the top of the .cshtml document:

• To use the Telerik UI for ASP.NET Core HtmlHelpers:

  @using Kendo.Mvc.UI
  

• To use the Telerik UI for ASP.NET Core TagHelpers:

  @addTagHelper *, Kendo.Mvc
  

Optionally, you can structure the document by adding the desired HTML elements like headings, divs, paragraphs, and others.

    @using Kendo.Mvc.UI

    <h4>RadioGroup with Predefined Items</h4>
    <br/>
    <div>

    </div>

    @addTagHelper *, Kendo.Mvc

    <h4>RadioGroup with Predefined Items</h4>
    <br/>
    <div>

    </div>

2. Initialize the RadioGroup

Use the RadioGroup HtmlHelper or TagHelper to add the component to a page:

• The Name() configuration method is mandatory as its value is used for the id and the name attributes of the RadioGroup element.
• The Items() collection contains the list of Items representing the available options.
• The Value() configuration applies the initial selection to a given item.

 @using Kendo.Mvc.UI

<h4>RadioGroup with Predefined Items</h4>
<br/>
<div>
    @(Html.Kendo().RadioGroup()
        .Name("radiogroup")
        .Items(i =>
        {
            i.Add().Label("Two bedroom apartment for multiple people").Value("1");
            i.Add().Label("Studio apartment with kitchen").Value("2");
            i.Add().Label("Double bed apartment with kids zone").Value("3");
        })
        .Value("2")
    )
</div>

@addTagHelper *, Kendo.Mvc

<h4>RadioGroup with Predefined Items</h4>
<br/>
<div>
        <kendo-radiogroup name="radiogroup"
                          radio-name="radiogroup"    
                          value="2">
            <kendo-radiogroup-items>
                <kendo-radiogroup-item label="Two bedroom apartment for multiple people" value="1"></kendo-radiogroup-item>
                <kendo-radiogroup-item label="Studio apartment with kitchen" value="2"></kendo-radiogroup-item>
                <kendo-radiogroup-item label="Double bed apartment with kids zone" value="3"></kendo-radiogroup-item>
            </kendo-radiogroup-items>
        </kendo-radiogroup>
</div>

3. Handle a RadioGroup Event

The RadioGroup component provides convenient events for implementing your desired logic. In this tutorial, you will use the exposed Change() event to log a new entry in the browser's console.

 @using Kendo.Mvc.UI

<script>
   function onChange(e) {
      console.log("Change :: old value: " + e.oldValue + ", new value: " + e.newValue);
   }
</script>

<h4>RadioGroup with Predefined Items</h4>
<br/>
<div>
    @(Html.Kendo().RadioGroup()
        .Name("radiogroup")
        .Items(i =>
        {
            i.Add().Label("Two bedroom apartment for multiple people").Value("1");
            i.Add().Label("Studio apartment with kitchen").Value("2");
            i.Add().Label("Double bed apartment with kids zone").Value("3");
        })
        .Value("2")
        .Events(e => e.Change("onChange"))
    )
</div>

@addTagHelper *, Kendo.Mvc

<script>
   function onChange(e) {
      console.log("Change :: old value: " + e.oldValue + ", new value: " + e.newValue);
   }
</script>

<h4>RadioGroup with Predefined Items</h4>
<br/>
<div>
        <kendo-radiogroup name="radiogroup" on-change="onChange"
                          radio-name="radiogroup"    
                          value="2">
            <kendo-radiogroup-items>
                <kendo-radiogroup-item label="Two bedroom apartment for multiple people" value="1"></kendo-radiogroup-item>
                <kendo-radiogroup-item label="Studio apartment with kitchen" value="2"></kendo-radiogroup-item>
                <kendo-radiogroup-item label="Double bed apartment with kids zone" value="3"></kendo-radiogroup-item>
            </kendo-radiogroup-items>
        </kendo-radiogroup>
</div>

4. (Optional) Reference Existing RadioGroup Instances

You can reference the RadioGroup instances that you have created and build on top of their existing configuration:

1. Use the id attribute of the component instance to establish a reference.

   <script>
       var radiogroupReference = $("#radiogroup").data("kendoRadioGroup"); // radiogroupReference is a reference to the existing RadioGroup instance of the helper.
   </script>
   

2. Use the RadioGroup client-side API to control the behavior of the widget. In this example, you will use the enable method to disable the RadioGroup.

   <script>
       var radiogroupReference = $("#radiogroup").data("kendoRadioGroup"); // radiogroupReference is a reference to the existing RadioGroup instance of the helper.
       radiogroupReference.enable(false); 
   </script>
   

Explore this Tutorial in REPL

You can continue experimenting with the code sample above by running it in the Telerik REPL server playground:

• Sample code with the RadioGroup HtmlHelper
• Sample code with the RadioGroup TagHelper

Next Steps

• Customize the Labels of the RadioGroup
• Configure the Layout

See Also

• Using the API of the RadioGroup for ASP.NET Core (Demo)
• Client-Side API of the RadioGroup
• Server-Side API of the RadioGroup
• Knowledge Base Section