<html>
<head>
<script>
function createTFoot()
{
var x=document.getElementById("myTable");
if (!x.tFoot)
{
var footer=x.createTFoot();
var row=footer.insertRow(0);
var cell=row.insertCell(0);
cell.innerHTML="<b>This is a table footer</b>";
}
}
function deleteTFoot()
{
document.getElementById("myTable").deleteTFoot();
}
</script>
</head>
<body>
<table id="myTable" border="1">
<tr>
<td>cell 1</td>
<td>cell 2</td>
</tr>
<tr>
<td>cell 3</td>
<td>cell 4</td>
</tr>
</table>
<br>
<button type="button" onclick="createTFoot()">Create tfoot</button>
<button type="button" onclick="deleteTFoot()">Delete tfoot</button>
</body>
</html>