vml画线后怎么删除！

和HTML一样删<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><html xmlns:v="urn:schemas-microsoft-com:vml">
<head>
<title>Thinking in VML</title>
</head>
<STYLE>
 v\:* { BEHAVIOR: url(#default#VML) }
</STYLE>
<body>
<div id="div1">&nbsp;</div>
<input type="button" onclick="delPoly()" value="删除">
<script language="javascript" type="text/javascript" defer>
var InsertLine="<v:PolyLine filled='false' strokeWeight=2.2pt strokeColor='red' Points='0,0 0,100 20,150 200,100' style='position:absolute'/>"; 
var newPoint = document.createElement(InsertLine); 
var ohye=document.getElementById("div1")
ohye.insertBefore(newPoint); 
function delPoly(){
newPoint.removeNode(true)
}
</script>
</body>