<script type="text/javascript">
 //隐藏层
  function reload(){
    document.getElementById("w").style.display="none";
    document.getElementById("q").style.display="block";
   
  }
   //隐藏层
  function remove(){
    document.getElementById("w").style.display="block";
    document.getElementById("q").style.display="none";
  
  }
</script>
<div id="w">
<input name="w"type="text">
</div>
<div id="q" style="display:none">
<input name="w" type="file"> <input type="button" value="取消" onclick="remove();"> 
</div>  
<input type="button" value="按钮" onclick="reload();">