<%@ Register Assembly="AsyncControls" Namespace="DelvingWare.AsyncControls" TagPrefix="dw" %>

<dw:AsyncRadioButton runat="server" ID="rbMain1" 
Text="Blue" 
Group="one"
OnCheckedChanged="rbMain_Checked" 
Value="blue" />
 
<dw:AsyncRadioButton runat="server" ID="rbMain2" 
Text="Green" 
Group="one"
OnCheckedChanged="rbMain_Checked" 
Value="green" />
 
<dw:AsyncRadioButton runat="server" ID="rbMain3" 
Text="Yellow" 
Group="one" 
OnCheckedChanged="rbMain_Checked" 
Value="yellow" />

<p/>

<dw:AsyncLabel runat="server" ID="lblMain" 
    Width="450" 
    RenderMode="div"
    CssClass="radioBtnLabel">Select a color.</dw:AsyncLabel>

using System;
using DelvingWare.AsyncControls;
...
protected void rbMain_Checked( object sender, AsyncEventArgs ae )
{
    // get the textual color value
    string color = (sender as AsyncRadioButton).Value;

    // change the color of the AsyncLabel
    lblMain.BackColor = System.Drawing.Color.FromName(color);

    // update the AsyncLabel text
    lblMain.Text = "AsyncLabel background color is now: "+ color;
}

Imports System
Imports DelvingWare.AsyncControls
...

Protected Sub rbMain_Checked(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' get the textual color value
    Dim color As String = CType(sender,AsyncRadioButton).Value
    ' change the color of the AsyncLabel
    lblMain.BackColor = System.Drawing.Color.FromName(color)
    ' update the AsyncLabel text
    lblMain.Text = ("AsyncLabel background color is now: " + color)
End Sub

.radioBtnLabel 

{
    margin-top: 20px;
    border: 3px ridge silver;
    padding: 5px 0px 5px 10px;
    font-family: Verdana, Arial, Serif;
    font-size: 12pt;
    font-weight: bold;
}