javascript 简单问题求解!!!
在如下一个简单的html页面,代码如下: 
  <html>  
  <body>  
  <table>  
  <tr   id= "t1 ">  
        <td>  <input   type= "text "   name= "a1 "   value= "a1 ">  </td>  
        <td>  <input   type= "text "   name= "b1 "   value= "b1 ">  </td>  
        <td>  <input   type= "button "   name= "submit1 "   value= "修改 ">  </td>  
  </tr>  
  <tr   id= "t2 ">  
        <td>  <input   type= "text "   name= "a2 "   value= "a2 ">  </td>  
        <td>  <input   type= "text "   name= "b2 "   value= "b2 ">  </td>  
        <td>  <input   type= "button "   name= "submit2 "   value= "修改 ">  </td>  
  </tr>  
  <tr   id= "t3 ">  
        <td>  <input   type= "text "   name= "a3 "   value= "a3 ">  </td>  
        <td>  <input   type= "text "   name= "b3 "   value= "b3 ">  </td>  
        <td>  <input   type= "button "   name= "submit3 "   value= "修改 ">  </td>  
  </tr>  
  </table>  
  </body>  
  </html>    
 我想当点击修改按钮时,   通过javascript获得当前行文本框中的值,例如: 
 当点击按钮submit1时,   得到文本框a1,b2中的值; 
 当点击按钮submit2时,   得到文本框a2,b2中的值等,   依次类推!!!   
 请各位大虾帮忙解决,   小弟不甚感激!!!!谢谢.......   
------解决方案-------------------- <html>  
  <script language= "JavaScript " type= "text/javascript ">  
   function getValue(obj) 
   { 
     var objTR = obj.parentNode.parentNode; 
 	var s1=objTR.cells[0].childNodes[0].value; 
     var s2=objTR.cells[1].childNodes[0].value; 
 	alert(s1+ "\n "+s2); 
   } 
  </script>  
  <body>  
  <table>  
  <tr id= "t1 ">  
    <td>  <input type= "text " name= "a1 " value= "a1 ">  </td>  
    <td>  <input type= "text " name= "b1 " value= "b1 ">  </td>  
    <td>  <input type= "button " name= "submit1 " value= "修改 " onclick= "getValue(this); ">  </td>  
  </tr>  
  <tr id= "t2 ">  
    <td>  <input type= "text " name= "a2 " value= "a2 ">  </td>  
    <td>  <input type= "text " name= "b2 " value= "b2 ">  </td>  
    <td>  <input type= "button " name= "submit2 " value= "修改 " onclick= "getValue(this); ">  </td>  
  </tr>  
  <tr id= "t3 ">  
    <td>  <input type= "text " name= "a3 " value= "a3 ">  </td>  
    <td>  <input type= "text " name= "b3 " value= "b3 ">  </td>  
    <td>  <input type= "button " name= "submit3 " value= "修改 " onclick= "getValue(this); ">  </td>  
  </tr>  
  </table>  
  </body>  
  </html>