Finally i was able to add a second header at run time on my gridview using OnRowCreated event....
using this article "http://www.dotnetfunda.com/codes/code280-creating-multiple-header-rows-in-gridview.aspx
if (e.Row.RowType == DataControlRowType.Header)
//adding the row
but the problem is that i can't add the header on the second header Row ( after the main header)
e second link was really usefull, but the problem is i can't add the second header at row only at row like this statement, if I replaced 0 with 1 the out of index exception will be fired
GridViewRow row = new GridViewRow(0, -1, DataControlRowType.Header, DataControlRowState.Normal);
if i replaced 1 with 0 in the code above an out of index exception is created.
is there any work around i can add the header on the second header row at postion ? ;