<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajaxToolkit" %><!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 runat="server"> <title>无标题页</title></head><body> <form id="form1" runat="server"> <div> <asp:ScriptManager ID="ScriptManager1" runat="server"> </asp:ScriptManager> </div> <asp:UpdatePanel ID="UpdatePanel1" runat="server"> <ContentTemplate> <asp:Label ID="Label1" runat="server" Text="Label" Width="166px"></asp:Label> <br /> <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" /> </ContentTemplate> </asp:UpdatePanel> <asp:UpdateProgress ID="testUp" runat=server AssociatedUpdatePanelID="UpdatePanel1"> <ProgressTemplate> progressing.. </ProgressTemplate> </asp:UpdateProgress> </form></body></html> 第三，在BUTTON中加入点击事件，代码如下： System.Threading.Thread.Sleep(5000); Label1.Text = DateTime.Now.ToString(); 主要是故意创建一个延迟，显示效果。最后，运行就ok了 相关文章： 2021-10-06 2022-12-23 2022-12-23 2021-06-15 2022-12-23 2021-07-09