效果图
以下为源码
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<ol start="5" reversed="8">
<li>nihao</li>
<li>nihao</li>
<li>nihao</li>
<li>nihao</li>
</ol>
<dl>
<dt>nihao</dt>
<dd>beijing</dd>
<dd>shenzhen</dd>
<dt>huijia</dt>
<dd><small>beijing</small></dd>
<dd><cite>shenzhen</cite></dd>
</dl>
<input type="text" autocomplete="on" list="test">
<datalist id="test">
<option>nihao</option>
<option>huanying</option>
<option>qingdao</option>
</datalist>
<script>
function yrdyd()
{
var control=document.getElementById("test");
var direction=control.selectionDirection;
alert(direction);
}
</script>
<form>
<input type="text" pattern="[A-Z]{3}" name="pattern">
<input type="submit"> <input type="text" name="pattern" id="test">
<input type="button" value="dianjiwo" onclick="yrdyd()">
</form>
</body>
</html>
其中control.selectionDirection不起作用，即每次alert(direction),都弹出提示underfine（用的是谷歌浏览器和火狐浏览器）,估计可能浏览器对该属性支持还不完善.