try something like
<head>
<script language="javascript">
function addColumn()
{
var rows = document.all("mytable").rows;
for (var i=0; i < rows.length; i++)
{
var cells = rows[i].cells;
var sum = 0.0;
for (var j=0; j < cells.length; j++)
{
var txt = cells[j].innerText;
if (!isNaN(txt))
sum += parseFloat(txt);
}
var cell = rows[i].insertCell();
cell.innerText = sum;
}
}
</script>
</head>
<body>
<table id="mytable" border="1" cellspacing="0" cellpadding="0">
<tr><td>1</td><td>1</td><td>1</td></tr>
<tr><td>2</td><td>2</td><td>2</td></tr>
<tr><td>3</td><td>3</td><td>3</td></tr>
<tr><td>4</td><td>4</td><td>4</td></tr>
</table>
<input type="button" value="add column" onclick="addColumn()">
</body>
<head>
<script language="javascript">
function addColumn()
{
var rows = document.all("mytable").rows;
for (var i=0; i < rows.length; i++)
{
var cells = rows[i].cells;
var sum = 0.0;
for (var j=0; j < cells.length; j++)
{
var txt = cells[j].innerText;
if (!isNaN(txt))
sum += parseFloat(txt);
}
var cell = rows[i].insertCell();
cell.innerText = sum;
}
}
</script>
</head>
<body>
<table id="mytable" border="1" cellspacing="0" cellpadding="0">
<tr><td>1</td><td>1</td><td>1</td></tr>
<tr><td>2</td><td>2</td><td>2</td></tr>
<tr><td>3</td><td>3</td><td>3</td></tr>
<tr><td>4</td><td>4</td><td>4</td></tr>
</table>
<input type="button" value="add column" onclick="addColumn()">
</body>
在帮我怎么删除表格的列吧