如何把放在 Ajax UpdatePanel 里面的控件给我揪出来!
把一个   Label1   放到   UpdatePanel   里面,   
 label   =   (Label)ctrl.FindControl( "Label1 ");   
 调试提示:label   为   null,运行出错:
未将对象引用设置到对象的实例。   
 但是只要把   Label1   拖到   UpdatePanel   外面,是没问题的!   
 大家帮帮忙吧。
------解决方案-------------------- <script runat= "server " language= "vb ">  
 Sub ttk(sender as object,e as system.eventargs) 
 Dim lb1 as label 
 lb=page.findcontrol( "label1 ") 
 lb.text= "你好,这是updatepanel里的label " 
 Eend sub 
  </script>    
  <form runat= "server ">  
  <asp:Updatepanel id= "update1 " ChildrenAsTriggers= "true " runat= "server " UpdateMode= "Always ">  
  <contenttemplate>  
  <asp:label runat= "server " ID= "label1 "/>  
     <cc1:popupwin id= "ppw " style= "Z-INDEX: 105; right: 0px; POSITION: absolute; TOP: 128px " runat= "server " width= "230px " height= "150px " windowsize= "300, 200 " windowscroll= "False " dockmode= "BottomLeft " colorstyle= "Blue " gradientdark= "210, 200, 220 " textcolor= "0, 0, 3 " shadow= "125, 90, 160 " lightshadow= "185, 170, 200 " darkshadow= "128, 0, 102 " visible= "False " showlink= "True " OffsetX= "0 ">  
  </cc1:popupwin>  
  <asp:Timer id= "tm1 " runat= "server " enabled= "true " interval= "10000 " ontick= "ttk ">  </asp:Timer>  
  </contenttemplate>  
  </asp:Updatepanel>  
  </form>
------解决方案--------------------他会每隔10秒更新label1的内容,你也可以把它改成 
 Sub ttk(sender as object,e as system.eventargs) 
 Dim lb1 as label 
 lb=page.findcontrol( "label1 ") 
 lb.text= "你好,这是updatepanel里的label " 
 Eend sub   
 to   
 Sub ttk(sender as object,e as system.eventargs) 
 Dim lb1 as label 
 lb=page.findcontrol( "label1 ") 
 lb.text=now() 
 Eend sub 
------解决方案--------------------Updatepanel 是要放一个 
 在body中 <asp:ScriptManager ID= "ScriptManager1 " runat= "server ">  </asp:ScriptManager>   	 
 控件才能使用 
------解决方案--------------------UpdatePanel控件熟悉?我也不是很熟悉!菜鸟 ! 
 下面的你参考!参考  
      <asp:UpdatePanel ID= "UpdatePanel1 " runat= "server " UpdateMode= "Conditional ">  
              <ContentTemplate>  
                  <asp:Button ID= "Button1 " runat= "server " OnClick= "Button1_Click " Text= "确定 " />  
                  <asp:Button ID= "Button2 " runat= "server " Text= "取消 " OnClick= "Button2_Click " />                   
                  <asp:Label runat= "server " ID= "InputTimeLabel ">  <%=DateTime.Now %>  </asp:Label>  
              </ContentTemplate>  
          </asp:UpdatePanel>  
------解决方案--------------------linjone()说得对 
 刚才忘记放 <asp:ScriptManager ID= "ScriptManager1 " runat= "server ">  </asp:ScriptManager>  
------解决方案--------------------Up
------解决方案--------------------