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(){
	alert(document.getElementById('myTable').tHead.innerHTML);
}
</script>
</head>
<body>

<table id="myTable" border="1">
	<thead>
		<tr>
			<th>Month</th>
			<th>Savings</th>
     	</tr>
	</thead>
   	<tfoot>
		<tr>
			<td>Sum</td>
			<td>$180</td>
     	</tr>
   </tfoot>
   <tbody>
	   <tr>
		   <td>January</td>
		   <td>$100</td>
	   </tr>
	   <tr>
		   <td>February</td>
		   <td>$80</td>
	   </tr>
	</tbody>
</table>
<br>
<button type="button" onclick="displayResult()">显示头部html文本</button>

</body>
</html>
源代码

动行结果
