在线运行代码 - 菜鸟教程

<!DOCTYPE html>
<html>
<head> 
<meta charset="utf-8"> 
<title>菜鸟教程(cainiaoplay.com)</title>
<script>
function displayResult(){
	var c=document.getElementById("myCol");
	alert("第二列对齐的字符是: " + c.ch);
}
</script>
</head>
<body>

<table border="1">
	<colgroup>
		<col>
		<col id="myCol" align="char" char=".">
  	</colgroup>
  	<tr>
		<th>月份</th>
		<th>存款</th>
  	</tr>
  	<tr>
		<td>January</td>
		<td>$100.00</td>
  	</tr>
  	<tr>
		<td>February</td>
		<td>$10.00</td>
  	</tr>
</table>
<br> 
<button type="button" onclick="displayResult()">获取字符对齐</button>
<p><b>注意:</b>不是所有的主流浏览器都支持char属性。</p>

</body>
</html>
源代码

动行结果
