​x
 
<!DOCTYPE html>
<html>
<head>
<script>
function padding(id) {
  document.getElementById(id).style.padding = "15px";
}
​
</script>
</head>
<body>
​
<table id="myTable" style="border:1px solid black">
  <tr>
    <td>100</td>
    <td>200</td>
  </tr>
  <tr>
    <td>300</td>
    <td>400</td>
  </tr>
</table>
​
<p>
<input type="button" onclick="padding('myTable')" value="更改内边距">
</p>
​
</body>
</html>
​