<ajaxToolkit:SlideShowExtender ID="SlideShowExtender1" runat="server"
TargetControlID="Image1"
SlideShowServiceMethod="GetSlides"
AutoPlay="true"
ImageDescriptionLabelID="imageLabel1"
NextButtonID="nextButton"
PlayButtonText="Play"
StopButtonText="Stop"
PreviousButtonID="prevButton"
PlayButtonID="playButton"
Loop="true" />

[System.Web.Script.Services.ScriptMethod]
WebService方法返回AjaxControlToolkit.Slide[]
public AjaxControlToolkit.Slide[] Silddeshow()
{
//Slide构造函数参数:new AjaxControlTookKit.Slide(string path,string name,string description) path:图片路径,name:图片名(自定义),description:图片的描述信息;在描述标签里文本显示格式为: name:description

AjaxControlToolkit.Slide s1 = new AjaxControlToolkit.Slide(@"images/Blue hills.jpg", "Blue hill", "Blue hill");
AjaxControlToolkit.Slide s2 = new AjaxControlToolkit.Slide(@"images/Sunset.jpg", "Sunset", "Sunset");
AjaxControlToolkit.Slide s3 = new AjaxControlToolkit.Slide(@"images/Water lilies.jpg", "Water lilies", "Water lilies");
AjaxControlToolkit.Slide s4 = new AjaxControlToolkit.Slide(@"images/Winter.jpg", "Winter", "Winter");
AjaxControlToolkit.Slide[] s = new AjaxControlToolkit.Slide[] { s1,s2,s3,s4};
return s;
}