Print only gridview data with preview using javascript

///  print grid data directly
function PrintGridData() {
var prtGrid = document.getElementById('<%=GDVBOQDetail.ClientID %>');
prtGrid.border = 0;
var prtgriddata = window.open('', 'GDVBOQDetail', 'left=100,top=100,width=1000,height=1000,tollbar=0,scrollbars=1,status=0,resizable=1');
prtgriddata .document.write(prtGrid.outerHTML);
prtgriddata .document.close();
prtgriddata .focus();
prtgriddata .print();
prtgriddata .close();
}

print preview then print


function PrintGridData() {
var prtGrid = document.getElementById('<%=GDVBOQDetail.ClientID %>');
prtGrid.border = 0;
var prtgriddata = window.open('', 'GDVBOQDetail', 'left=100,top=100,width=1000,height=1000,tollbar=0,scrollbars=1,status=0,resizable=1');
prtgriddata .document.write(prtGrid.outerHTML);
prtgriddata .document.close();
prtgriddata .focus();
//prtgriddata .print();
//prtgriddata .close();
}