Question

I upload an image with AsyncFileUpload control.

On UploadedComplete I try to assign some value to a hidden field using ScriptManager.RegisterClientScriptBlock.

html:

<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" CombineScripts="false">
</asp:ToolkitScriptManager> 
<div>
    <asp:AsyncFileUpload ID="uplImage" OnUploadedComplete="uplImage_UploadedComplete"
        runat="server" Width="285px" ClientIDMode="AutoID" EnableViewState="false" />
    <asp:HiddenField runat="server" ID="hdnTempImgNm" />      
    <input type="button" id="btnCheck" value="Check" class="btnCheck" />
</div>

event handler:

protected void uplImage_UploadedComplete(object sender, EventArgs args)
    {
        //1 case:
        //ScriptManager.RegisterClientScriptBlock(uplImage, uplImage.GetType
        //  (), "myscript",
        //String.Concat(" $(document).ready(function(){$('input:hidden
        //   [name*=\"hdnTempImgNm\"]').val('Some value');})"),true);

        //2 case:
        ScriptManager.RegisterClientScriptBlock(uplImage, uplImage.GetType
        (), "myscript",
        String.Concat("top.document.getElementById('" + hdnTempImgNm.ClientID 
         + "').value='Some value'; "),true);
    }

javascript:

 <script>
    $(document).ready(function () {    
        $('.btnCheck').click(function (e) {
            alert($('input:hidden[name*="hdnTempImgNm"]').val());
        });
    })
</script>

In the 1 case when I click on the Check button to check a hidden filed value I get an empty value. But in the 2 case where I use top.document I get the right value i.e. “Some value”.

My questions are:
1. Why the 1 case doesn’t work?
2. How can I rewrite the 2 case using jquery (i.e. how to write top.document)?

Thank you

Answer 1

AsyncFileUpload is using iframe. Because of that only top.document works in this case.
See link http://www.mikeborozdin.com/post/AJAX-File-Upload-in-ASPNET-with-the-AsyncFileUpload-Control.aspx

So the first case should be like this

ScriptManager.RegisterClientScriptBlock(uplImage, uplImage.GetType(), “myscript”, String.Concat(” $(document).ready(function(){$(‘input:hidden[name*=\”hdnTempImgNm\”]’, window.parent.document).val(\”Some value\”);})”),true);