リストボックスの内容を変更

Pattern1 Pattern2
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title></title>
<script type="text/javascript">
<!--
var arr1 = new array("1-1", "1-2");
var arr2 = new array("2-1", "2-2");
var lngL = 2;
var i    = 0;
function Flg(intF){
	for (i = 0; i < lngL; i++){
		if (intF == 1){
			document.forms["f1"].elements["listB"].options[i].text = arr1[i];
		}else{
			document.forms["f1"].elements["listB"].options[i].text = arr2[i];
		}
	}
}
//-->
</script>
</head>
<body onLoad="Flg(1)">
<form name="f1">
<input type="radio" name="r1" value="r1" checked onClick="Flg(1)">Pattern1
<input type="radio" name="r1" value="r2" onClick="Flg(2)">Pattern2
<select size="2" name="listB">
<option></option>
<option></option>
</select>
</form>
</body>
</html>