实际应用中要实现A页面跳转到B页面,B页面Load中执行一些耗时的图片处理操作,然后将处理后的图片显示出来,为了让B页面先正常展现,让后再加载数据,需要使用到VS2010中的AJAX控件:ScriptManager,UpdatePanel,Timer,UpdateProgress。

B页面代码:

<form id="form1" runat="server">
    <div style="margin:0 auto;">
        <asp:ScriptManager ID="ScriptManager1" runat="server">
        </asp:ScriptManager>   
            <asp:UpdateProgress ID="UpdateProgress1" runat="server">
            <ProgressTemplate>
                <div style="margin:0 auto;">
                    <img src="img/loading.gif" alt="Wait" />
                </div>
            </ProgressTemplate>
        </asp:UpdateProgress>
        <asp:UpdatePanel ID="UpdatePanel1" runat="server">
            <ContentTemplate>              
                <asp:Image ID="Image1" runat="server" ImageUrl="~/img/logo.png" 
                ImageAlign="Middle" /></ContentTemplate>
                <Triggers>
                <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" />
                </Triggers>
        </asp:UpdatePanel>
    </div>
    <div style="height:50px">
        <asp:Timer ID="Timer1" runat="server" ontick="Timer1_Tick" Interval="1000">
                </asp:Timer>
    </div>
    </form>