如何用JAVASCRIPT DOM,取得最后一td节点
<html>  
  <head>  
  <script   type= "text/javascript "   src= "tx.js ">  </script>  
  </head>  
  <body>  
 	 <input   type= "hidden "   name= "jsp_name "   value= "../proc.jsp ">  
 	 <table   width= "98% "   border= "0 "   cellspacing= "0 "   cellpadding= "0 ">  
       		 <tr>  
             		 <td   height= "13 ">   </td>  
       		 </tr>  
       		 <tr>  
             		 <td   class= "td_title1 "> 职工基本信息表 </td>  
       		 </tr>  
       		 <tr>  
             		 <td   height= "13 ">   </td>  
       		 </tr>  
       		 <tr>  
             		 <td   class= "td_title2 "> 增加职工基本信息 </td>  
       		 </tr>  
       		 <tr>  
             		 <td   height= "13 ">   </td>  
       		 </tr>  
       		 <tr>  
             		 <td   height= "25 ">   </td>  
       		 </tr>  
       		 <tr>  
             		 <td   height= "25 "   align= "center ">  
             			 <img   src= "../img/queding.jpg "   onClick= "sub_mit() ">  
             			 <img   src= "../img/chongxie.jpg "   onClick= "re_set() ">  
 			 </td>  
       		 </tr>  
 	 </table>  
  </body>  
  </html>
------解决方案--------------------t = document.getElementById( "tableid ") 
 alert(t.rows[t.rows.length-1].cells[t.rows[t.rows.length-1].cells.length-1].innerHTML)
------解决方案--------------------var tds = document.getElementsByTagName( "TD "); 
 var LastTd = tds[tds.length-1];   
 全文档的最后一个TD出来了
------解决方案--------------------  t = document.getElementsByTagName( "table ")[0] 
 alert(t.childNodes[0].childNodes.length);   
 bb.childNodes[0]是tbody 
 每个table都会自动生成一个tbody,tr是tbody下面的 
  <table>  
  <tbody>  
  <tr>  
  </tr>  
  </tbody>  
  </table>
------解决方案--------------------另外如果知道table元素,获取当前table的最后一个td也有很多方法   
 方法1: 
 var lastTd = tableElement.cells[tableElements.cells.length-1];   
 方法2: 
 var tds = tableElement.getElementsbyTagName( "TD "); 
 var lastTd = tds[tds.length-1];   
 这2种都是最简单的方法.