我是这样使用Ajax进度条的

在模版页DefaultMaster.master页中:

<asp:Panel ID="UpdateProgressPanel" runat="server">
<asp:UpdateProgress ID="uprog" runat="server">
<ProgressTemplate>
<div class="Progress">
<%= Resources.GResource.Updating %>
<br />
<asp:Image ID="UpdateProgressImage" runat="server" ImageUrl="~/Images/PleaseWait.gif" />
</div>
</ProgressTemplate>
</asp:UpdateProgress>
</asp:Panel>
<ajax:AlwaysVisibleControlExtender ID="UpdateProgressAlwaysVisibleControlExtender" runat="server" HorizontalOffset="300" HorizontalSide="Left" ScrollEffectDuration=".1" TargetControlID="UpdateProgressPanel" VerticalOffset="300" VerticalSide="Top">
</ajax:AlwaysVisibleControlExtender>

CSS:

.Progress
{
background-color: Green;
color: #ffffff;
}

这样进度条就永远可见了 屏幕截图如下:

PleaseWait.gif