JavaScript表单验证

<script language="javascript">
function change(){
if(form1.name2.value=="3"&&form1.name2.value!="3"){
alert("afa");
}
}
</script>
<form name="form1">
<select name='name1'>
<option selected value=''>请选择</option>
<option value='1>1</option>
<option value='2'>2</option>
<option value='3'>3</option>
</select>
<select name='name2'>
<option selected value=''>请选择</option>
<option value='1>1</option>
<option value='2'>2</option>
<option value='3'>3</option>
</select>
</form>

如果你是要求这个下拉菜单的值一样的话可以这样写
<script language=javascript>
<!--
function check()
{
if(name1.value!=name2.value){<