<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="http://common.cnblogs.com/script/jquery.js"
    type="text/javascript"></script>
<title>jQuery</title>
</head>
<body>
    <table width=500 border=2>
        <tr><td width=250>序号</td><td width=250>项目</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
        <tr><td></td><td>Port</td></tr>
    </table>
</body>
</html>
$(function(){
        //$('table tr:not(:first)').remove();
        var len = $('table tr').length;
        for(var i = 1;i<len;i++){
            $('table tr:eq('+i+') td:first').text(i);
        }       
});