改变input属性

<script language=javascript>
function Select01(){
if (document.form1.Select02.options.value=="1") {
document.form1.input01.readOnly=true;
document.form1.input01.style.background="#f3f3f3";
}
if (document.form1.Select02.options.value=="2") {
document.form1.input01.readOnly=false;
document.form1.input01.style.background="";

}
}
</script>
<form name="form1">
<select name="Select02"  onchange="return Select01();">
<option value="">选择</option>
<option value="1">1</option>
<option value="2">2</option>
< lect>
<input type=text name="input01" value="" >
</form>