<html>
<head>
<script type="text/javascript">
function disable()
{
document.getElementById("mySelect").disabled=true
}
function enable()
{
document.getElementById("mySelect").disabled=false
}
</script>
</head>
<body>
<form>
<select id="mySelect">
<option>苹果</option>
<option>桃子</option>
<option>香蕉</option>
<option>桔子</option>
</select>
<br /><br />
<input type="button" onclick="disable()" value="禁用列表">
<input type="button" onclick="enable()" value="启用列表">
</form>
</body>
</html>
