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File: ImageRotator.cs
using System;
using System.Collections;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.ComponentModel;
namespace myControls
{
[ParseChildren(true, "ImageItems")]
public class ImageRotator : WebControl
{
private ArrayList _imageItems = new ArrayList();
public ArrayList ImageItems
{
get
{
return _imageItems;
}
}
protected override void RenderContents(HtmlTextWriter writer)
{
if (_imageItems.Count > 0)
{
Random rnd = new Random();
ImageItem img = (ImageItem)_imageItems[rnd.Next (_imageItems.Count)];
writer.AddAttribute(HtmlTextWriterAttribute.Src, img.ImageUrl);
writer.AddAttribute(HtmlTextWriterAttribute.Alt, img.AlternateText);
writer.RenderBeginTag(HtmlTextWriterTag.Img);
writer.RenderEndTag();
}
}
}
public class ImageItem
{
private string _imageUrl;
private string _alternateText;
public string ImageUrl
{
get { return _imageUrl; }
set { _imageUrl = value; }
}
public string AlternateText
{
get { return _alternateText; }
set { _alternateText = value; }
}
}
}
File: ShowImageRotator.aspx
<%@ Page Language="C#" Trace="true" %>
<%@ Register TagPrefix="custom" Namespace="myControls" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Show ImageRotator</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<custom:ImageRotator
id="ImageRotator1"
Runat="server">
<custom:ImageItem ImageUrl="Image1.gif" AlternateText="Image 1" />
<custom:ImageItem ImageUrl="Image2.gif" AlternateText="Image 2" />
<custom:ImageItem ImageUrl="Image3.gif" AlternateText="Image 3" />
</custom:ImageRotator>
</div>
</form>
</body>
</html>
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