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

<dw:AsyncButton runat="server" ID="btVisible"
CssClass="greyButton"
Text="Hide AsyncImage"
OnClick="btVisible_Click" />
<p/>
<dw:AsyncImage runat="server" ID="imgMain" 
ImageUrl="../images/imageIcon.gif"
OnClick="imgMain_Click" 
OnMouseOut="imgMain_MouseOut" 
OnMouseOver="imgMain_MouseOver" />

<dw:AsyncButton runat="server" ID="btMain" 
CssClass="greyButton"
Text="Show Random Image" 
OnClick="btMain_Click" />

<dw:AsyncLabel runat="server" ID="lblMain" 
RenderMode="bold" />

using System;
using DelvingWare.AsyncControls;
...
string [] imgUrls = { "../images/TabPanelIcon.gif", "../images/SlidePanelIcon.gif", "../images/PageRepeaterIcon.gif" };

protected void imgMain_MouseOut( object sender, AsyncEventArgs ae )
{
    // update the AsyncLabel
    lblMain.Text = "Mouse out.";
}

protected void imgMain_MouseOver( object sender, AsyncEventArgs ae )
{
    // update the AsyncLabel
    lblMain.Text = "Mouse over.";
}

protected void imgMain_Click( object sender, AsyncEventArgs ae )
{
    // update the AsyncLabel
    lblMain.Text = "Image clicked.";
}

protected void btMain_Click( object sender, AsyncEventArgs ae )
{
    // get a random index
    int index = new Random().Next(imgUrls.Length);

    // update the image source url
    imgMain.ImageUrl = imgUrls[index];
}

protected void btVisible_Click( object sender, AsyncEventArgs ae )
{
    // update the AsyncButton
    if ( imgMain.Visible )
        btVisible.Text = "Show AsyncImage";
    else
        btVisible.Text = "Hide AsyncImage";

    // toggle visibility
    imgMain.Visible = !imgMain.Visible;
}

Imports System
Imports DelvingWare.AsyncControls
...Dim imgUrls() As String
  
Protected Sub imgMain_MouseOut(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' update the AsyncLabel
    lblMain.Text = "Mouse out."
End Sub

Protected Sub imgMain_MouseOver(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' update the AsyncLabel
    lblMain.Text = "Mouse over."
End Sub

Protected Sub imgMain_Click(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' update the AsyncLabel
    lblMain.Text = "Image clicked."
End Sub

Protected Sub btMain_Click(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' get a random index
    Dim index As Integer = (New Random + Next(imgUrls.Length))
    ' update the image source url
    imgMain.ImageUrl = imgUrls(index)
End Sub

Protected Sub btVisible_Click(ByVal sender As Object, ByVal ae As AsyncEventArgs)
    ' update the AsyncButton
    If imgMain.Visible Then
        btVisible.Text = "Show AsyncImage"
    Else
        btVisible.Text = "Hide AsyncImage"
    End If
    ' toggle visibility
    imgMain.Visible = Not imgMain.Visible
End Sub