设置UpdateProgress控件的AssociatedUpdatePanelID为第2步 UpdatePanel的ID（如果页面中有多个UpdatePanel则，只有相应updatePanel关联的updateProgress显示）
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Untitled Page</title>
<style type="text/css">
#UpdatePanel1, #UpdatePanel2, #UpdateProgress1 {
border-right: gray 1px solid; border-top: gray 1px solid;
border-left: gray 1px solid; border-bottom: gray 1px solid;
}
#UpdatePanel1, #UpdatePanel2 {
width:200px; height:200px; position: relative;
float: left; margin-left: 10px; margin-top: 10px;
}
#UpdateProgress3 {
width: 200px; background-color: #FFC080;
bottom: 0%; left: 0px; position: absolute;
}
#UpdateProgress2 {
width: 200px; background-color: #FFC080;
bottom: 0%; left: 0px; position: absolute;
}
</style>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click1" Text="Button" />
<asp:Label ID="Label1" runat="server" Text="显示数据"></asp:Label>
<asp:UpdateProgress ID="UpdateProgress1" runat="server" AssociatedUpdatePanelID="UpdatePanel1">
<ProgressTemplate>
<div id="progress"><img src="img/1.gif" />
等待中...
</div>
</ProgressTemplate>
</asp:UpdateProgress>
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="UpdatePanel2" runat="server">
<ContentTemplate>
<asp:Button ID="Button2" runat="server" OnClick="Button2_Click1" Text="Button" /><br />
<br />
<asp:Label ID="Label2" runat="server" Text="显示数据"></asp:Label>
<asp:UpdateProgress ID="UpdateProgress2" runat="server" AssociatedUpdatePanelID="UpdatePanel2">
<ProgressTemplate>
更新数据中....
</ProgressTemplate>
</asp:UpdateProgress>
</ContentTemplate>
</asp:UpdatePanel>
</form>
</body>
</html>
