ASP.NET在更新面板更新时显示“正在加载...”消息

Question

Hello I am creating an ASP.NET/C# application I have an update panel that takes time to update. Is there a way to display a "Loading... Please Wait" Message during the time of the calculations?

Currently I am using AJAX panel animation fade in/fade out, to make the panel disappear while calculating and then reappear when done. But that is not very practical.

I need to display a message if possible.

Thank you for any help.

this is the code of my panel:

<asp:UpdatePanel ID="UpdatePanel1" runat="server">
    <Triggers>
        <asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click"/>
    </Triggers>
    <ContentTemplate>
        //Contents goes here
    </ContentTemplate>
</asp:UpdatePanel>

And the Ajax Panel animation extender

<ajaxToolkit:UpdatePanelAnimationExtender ID="UpdatePanelAnimationExtender1" runat="server" TargetControlID="UpdatePanel1">
    <Animations>
        <OnUpdating>
            <FadeOut Duration="1" Fps="20" />
        </OnUpdating>
        <OnUpdated>
            <FadeIn Duration="2" Fps="20" />
        </OnUpdated>
    </Animations>
</ajaxToolkit:UpdatePanelAnimationExtender>

Answer 1

You can use code as below when

using Image as Loading

<asp:UpdateProgress id="updateProgress" runat="server">
    <ProgressTemplate>
        <div style="position: fixed; text-align: center; height: 100%; width: 100%; top: 0; right: 0; left: 0; z-index: 9999999; background-color: #000000; opacity: 0.7;">
            <asp:Image ID="imgUpdateProgress" runat="server" ImageUrl="~/images/ajax-loader.gif" AlternateText="Loading ..." ToolTip="Loading ..." style="padding: 10px;position:fixed;top:45%;left:50%;" />
        </div>
    </ProgressTemplate>
</asp:UpdateProgress>

using Text as Loading

<asp:UpdateProgress id="updateProgress" runat="server">
    <ProgressTemplate>
        <div style="position: fixed; text-align: center; height: 100%; width: 100%; top: 0; right: 0; left: 0; z-index: 9999999; background-color: #000000; opacity: 0.7;">
            <span style="border-width: 0px; position: fixed; padding: 50px; background-color: #FFFFFF; font-size: 36px; left: 40%; top: 40%;">Loading ...</span>
        </div>
    </ProgressTemplate>
</asp:UpdateProgress>

Answer 2

令人敬畏的教程： 3种不同的方式来显示ASP.NET AJAX应用程序的进展

Answer 3

You can use the UpdateProgress control:

Also see: ajax "loading" icon with UpdatePanel postbacks