Possible Duplicate:
File Upload Control is not working
I have a web page with FileUpload control, Image control to display uploaded file, DataList control to display results of the query. There is a single button to trigger processing: saving image from upload control and passing it for processing to find image matches and displaying them in a grid view control.
I wanted to perform the whole operation flicker free and put all controls into
<asp:UpdatePanel ID=”UpdatePanel1” runat=”server”>
<ContentTemplate>
...
</ContentTemplate>
</asp:UpdatePanel>
However upon the button click file upload control does not have file. Do I need to separate file upload and image processing logic into 2 buttons from which file upload can not be performed without full page postback?
Use AjaxFileUpload from AJAX control toolkit. You can find the documentation here: http://www.asp.net/ajaxLibrary/AjaxControlToolkitSampleSite/AjaxFileUpload/AjaxFileUpload.aspx