ExtJs的el和contentEl的区别
1、把<div id="div_exam"></div>嵌入到当前Ext元素panel内:


Js代码
{  
     fieldLabel: "上传图片",  
          xtype: 'panel',  
     contentEl: 'div_exam' 
} 

{
     fieldLabel: "上传图片",
          xtype: 'panel',
     contentEl: 'div_exam'
}
效果:

Html代码
<div class="x-panel-body x-panel-body-noheader" id="ext-gen155" style="width: 500px;"> 
      <div id="div_exam"></div> 
</div> 

<div class="x-panel-body x-panel-body-noheader" id="ext-gen155" style="width: 500px;">
      <div id="div_exam"></div>
</div>

2、.把当前Ext元素panel嵌入到<div id="div_exam"></div>内

Js代码
{  
      fieldLabel: "上传图片",  
              width: 200,  
              xtype: 'panel',  
                    el: 'div_exam' 

{
       fieldLabel: "上传图片",
               width: 200,
               xtype: 'panel',
                     el: 'div_exam'
}
效果:

Html代码
<div id="div_exam"> 
      <div class="x-panel-body x-panel-body-noheader" id="ext-gen155" style="width: 500px;">....</div> 
</div>