Print Gridview using JavaScript

<script  type="text/javascript">

        function CallPrint(strid) {

            var prtContent = document.getElementById(strid);

            var WinPrint = window.open('', '', 'letf=0,top=0,width=900,height=600,toolbar=1,scrollbars=1,status=1');

            WinPrint.document.write(prtContent.innerHTML);

            WinPrint.document.close();

            WinPrint.focus();

            WinPrint.print();

            prtContent.innerHTML = strOldOne;

            WinPrint.close();

        }

    </script>

<input id="btnPrint" onclick="javascript: CallPrint('divPrint')" type="button" value="Print" visible="True" />

<div id="divPrint" align="center">

            <asp:GridView ID="GridView2" runat="server"></asp:GridView>

</div>