缺少对象
<tr>  
  <TD>  
  <IMG   src= "images/2.jpg "   onclick   =    "showDiv( 'div_used ') "   >  <IMG   src= "images/3.jpg "   onclick   =    "showDiv( 'div_current ') "> 2。当点击这两个图片时,再显示div里的图片。现在这行老是报错“缺少对象” 
  </TD>  
  </tr>  
  <tr>  
  <td>  
  <div   id   =    "div_current "   style   =    "display:block; ">  <img   src= "images/banner.jpg "> 1。进入该html页时,先显示该图片。 
  </div>  
  <div   id   =    "div_used "   style   =    "display:none; ">  <img   src   =    "images/4.jpg ">  
  </div>  
  </td>  
  </tr>  
 ********************************* 
 3。JS 
 function   showDiv(divID) 
 { 
 	var   id   =   document.getElementById(divID); 
 	if(id   ==    'div_current ') 
 	{ 
 		div_current.style.display   ==    "block "; 
 		div_used.style.display   ==    "none "; 
 	} 
 	else 
 	{ 
 		div_used.style.display   ==    "block "; 
 		div_current.style.display   ==    "none "; 
 	} 
 }   
 请大家帮帮忙,谢谢。
------解决方案--------------------function showDiv(divID) 
 { 
 if(divID ==  'div_current ') 
 { 
 div_current.style.display ==  "block "; 
 div_used.style.display ==  "none "; 
 } 
 else 
 { 
 div_used.style.display ==  "block "; 
 div_current.style.display ==  "none "; 
 } 
 }
------解决方案--------------------var id = document.getElementById(divID); 
 	if(id ==  'div_current ') 
 这句话有问题啊! 
 你定义的id是一个object,而div_current看样子是个变量
------解决方案--------------------id = document.getElementById(divID)得到的是一个对象,不能与字符串比较
------解决方案-------------------- <!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>  
      <title> Untitled Page </title>  
  </head>  
  <body>  
      <table>  
          <tr>  
              <td style= "width: 398px; height: 136px "> div_used 
                  <img src= "images/2.jpg " onclick= "showDiv( 'div_used ') " height= "50 " width= "50 ">  </td>  
              <td style= "width: 398px; height: 136px "> div_current 
                  <img src= "images/3.jpg " onclick= "showDiv( 'div_current ') " height= "50 " width= "50 ">  </td>  
          </tr>  
          <tr>  
              <td style= "width: 398px; height: 138px ">  
                  <div id= "div_current " style= "display: block; "> div_current 
                      <img src= "images/banner.jpg " height= "50 " width= "50 ">  
                  </div>  
              </td>  
              <td style= "width: 398px; height: 138px ">  
                      <div id= "div_used " style= "display: none; "> div_used 
                          <img src= "images/4.jpg &q