on your asyncfileupload bind OnUploadedComplete event to the method
OnUploadedComplete = "FileUploded"
code:
protected Sub FileUploded(object sender, EventArgs e)
Dim fu AjaxControlToolkit.AsyncFileUpload
Dim row As GridViewRow = CType(fu.NamingContainer, GridViewRow)
Dim idx = row.RowIndex
fu = ctype(sender,AjaxControlToolkit.AsyncFileUpload)
If fu.HasFile then
--do something--
End If
End Sub
c#:
protected void FileUploded(object sender, EventArgs e)
{
AsyncFileUpload fu = (AjaxControlToolkit.AsyncFileUpload)sender;
GridViewRow row = (GridViewRow)fu.NamingContainer;
string idx = row.RowIndex.toString();
}