示例：
- - - - - - - - - - - -
<body>
<input type="button" value="create" onclick="createTr();">
<table border='1' id="t" >
</table>
<input type="button" value="提交" onclick="okss();" />
</body>
<script type="text/javascript">
function createTr()
{
var tab = document.getElementById("t");
//create tr
for(var j=0;j<3;j++) {
var tr = tab.insertRow();
//create td
var td1 = tr.insertCell(0);
td1.innerHTML = "test"+j;
var td2 = tr.insertCell(1);
td2.innerHTML = "<input type='text' id='td_"+j+"' class='input' size='5' >";
