Hello,

the title says it all. I have seen some similar questions on SO like this or this, but either i have overlooked something or my requirement is different, neither works.

My situation is following:

• i have a Masterpage
• one of its contentpage is called MasterData.aspx
• MasterData has an asp.net ajax tabcontainer control with one usercontrol in every tabpanel
• these usercontrols(f.e. MD_Customer.ascx)hold the main content(like a normal page)
• they all have GridViews in it and i want to provide an Excel-Export-Button

What i've tried is is to use an iframe like here. But the function that adds the iframe to the document gets never called and therefore i never see the save-as-dialog. Maybe this is caused by using a MasterPage.

Does somebody has an idea on how to provide a button in an UpdatePanel that causes an async postback, so that i can generate a CSV dynamically in codebehind and write it to the response?

Thank you in advance.

aspx-markup:

<asp:UpdatePanel ID="UpdGridInfo" runat="server" >
    <ContentTemplate>
       <asp:Label ID="LblInfo"  Font-Underline="false"  runat="server" CssClass="content" ></asp:Label>&nbsp;&nbsp;
       <asp:ImageButton ToolTip="export to Excel" style="vertical-align:bottom" ID="BtnExcelExport" ImageUrl="~/images/excel2007logo.png" runat="server" />
    </ContentTemplate>
</asp:UpdatePanel>

and the BtnExportExcel codebehind handler(of course it cannot work to write the csv to the response of this page):

   Private Sub BtnExcelExport_Click(ByVal sender As Object, ByVal e As System.Web.UI.ImageClickEventArgs) Handles BtnExcelExport.Click
        Dim csv As String = tableToCsv(DirectCast(Me.GridSource, DataTable))
        Response.AddHeader("Content-disposition", "attachment; filename=RuleConfigurationFile.csv")
        Response.ContentType = "application/octet-stream"
        Response.Write(csv)
        Response.End()
    End Sub