code to print text entered in textbox

<script language="javascript" type="text/javascript">
                function CallPrint(strid) {
                    var prtContent = document.getElementById(strid);
                    var WinPrint = window.open('', '', 'letf=0,top=0,width=1,height=1,toolbar=0,scrollbars=0,status=0');
                    WinPrint.document.write(prtContent.innerHTML);
                    WinPrint.document.close();
                    WinPrint.focus();
                    WinPrint.print();
                    WinPrint.close();
                    prtContent.innerHTML = strOldOne;
                }
</script>

<div id="bill">
<asp:textbox id="TextBox1" runat="server" textmode="MultiLine" height="224px" xmlns:asp="#unknown">
            style="margin-bottom: 136px" Width="320px"></asp:textbox>
</div>

<asp:button id="BtnPrint" runat="server" text="Print" onclientclick="javascript:CallPrint('bill');"  />
</div>