JavaScript表格编辑功能实现方法

<html>
<head>
<script type="text/javascript">
function getInnerHTML()
{
alert(document.getElementById("tr2").innerHTML);
}
 
function insCell()
{
 var x=document.getElementById('tr2').insertCell(0)
 x.innerHTML="Table Row, Table Cell"
}
 
function delCell()
{
 document.getElementById('tr2').deleteCell(0)
}
 
function deleteCaption()
{
 document.getElementById('myTable').deleteCaption()
}
 
function createCaption()
{
var x=document.getElementById('myTable').createCaption()
x.innerHTML="My Table"
}
 
function delRow()
{
document.getElementById('myTable').deleteRow(0)
}
 
function insRow()
{
var x=document.getElementById('myTable').insertRow(0);
var y=x.insertCell(0);
var z=x.insertCell(1);
y.innerHTML="New Cell 1";
z.innerHTML="New Cell 2";
}
</script>
</head>
<body>
<center><table id="myTable" border="1">
<tr id="tr2">
<td>Row1 cell1</td>
<td>Row1 cell2</td>
</tr>
<tr id="tr2">
<td>Row2 cell1</td>
<td>Row2 cell2</td>
</tr>
<tr id="tr2">
<td>Row3 cell1</td>
<td>Row3 cell2</td>
</tr>
</table>
<br />
<center>
<table border="0">
<tr><th colspan="2">Table Controler</th></tr>
<tr><td>
<center>
<input type="button" onclick="createCaption()" 
value="Create caption"></td><td>
<center>
<input type="button" onclick="deleteCaption()"
value="Delete caption" />
</td></tr>
<tr><td colspan="2">
<center>
<input type="button" onclick="getInnerHTML()"
value="Alert innerHTML of table row" />
</td></tr>
<tr><td>
<center>
<input type="button" onclick="insRow()" 
value="Insert row">
</td><td>
<center>
<input type="button" onclick="delRow()"
value="Delete first row">
</td></tr>
<tr><td>
<center>
<input type="button" onclick="insCell()" 
value="Insert cell">
</td><td>
<center>
<input type="button" onclick="delCell()" 
value="Delete cell">
</td></tr>
</table>
</body>
</html>