js 打印效能

function printInfo() {
	var printId = document.getElementById("print");
	var mStr = window.document.body.innerHTML ;           
	window.document.body.innerHTML =printId.innerHTML; 
	window.print(); 
	window.document.body.innerHTML = mStr; 
}
function printView() {
//打印预览
	var wb = document.getElementById('wb');
	wb.ExecWB(7,1);
}

<OBJECT classid="CLSID:8856F961-340A-11D0-A96B-00C04FD705A2" height="0" id="wb" name="wb" width="0"></OBJECT> 
<div id="printDiv">需要打印的内容</div>