<asp:Button runat="server" ID="SubmitButton" OnClientClick="return submitbutton_click()"
                        Text="Submit" OnClick="SubmitButton_Click" />

    <script type="text/javascript">
function submitbutton_click() {
    var submitbutton = document.getElementById('<%=SubmitButton.ClientID %>');
    var uploadobj = document.getElementById('<%=Uploader1.ClientID %>');
    if (!window.filesuploaded) {
        if (uploadobj.getqueuecount() > 0) {
            uploadobj.startupload();
        }
        else {
            var uploadedcount = parseInt(submitbutton.getAttribute("itemcount")) || 0;
            if (uploadedcount > 0) {
                return true;
            }
            alert("Please select the GPCM database to upload.");
        }
        return false;
    }
    window.filesuploaded = false;
    return true;
}

function CuteWebUI_AjaxUploader_OnPostback() {
    window.filesuploaded = true;
    var submitbutton = document.getElementById('<%=SubmitButton.ClientID %>');
    submitbutton.click();
    return false;
}
    </script>