UpdatePanel最简单的用法（实现页面图片的局部刷新）

例子：本例子的图片的名字是从1~5.jpg

aspx代码

<asp:UpdatePanel ID="UpdatePanel2" runat="server">                

<Triggers>              

 <asp:AsyncPostBackTrigger ControlID="Timer3" EventName="Tick"/>    //可以不指定事件名，controlID用来指定所要触发的控件              

</Triggers>                

<ContentTemplate>                    

 <asp:Image ID="Image4" runat="server" ImageUrl="~/piclv/1.jpg" Height="275px"   Width="573px"/>                    

 <asp:ScriptManager ID="ScriptManager2" runat="server">//可以写在UpdatePanel外面              

</asp:ScriptManager>                   

 <asp:Timer ID="Timer3" runat="server" ontick="Timer3_Tick" Interval="2000">                    

</asp:Timer>                

 </ContentTemplate>                

 </asp:UpdatePanel>    

 cs代码：       

 static int a = 1;        

 protected void Timer3_Tick(object sender, EventArgs e)        

 {            

           Image4.ImageUrl = "~/piclv/" + a + ".jpg";            

           a++;            

          if (a == 6)            

          {                

              a = 1;            

          }        

}