JavaScript实现按钮点击切换元素显示与隐藏

<html>
<head>
<meta charset="gb2312">
<title>隐藏和显示</title>
<style type="text/css">
#thediv
{
 width:200px;
 height:100px;
 line-height:100px;
 text-align:center;
 background-color:green;
}
</style>
<script type="text/javascript">
function Show_Hidden(obj)
{
 if(obj.style.display=="block")
 {
  obj.style.display='none';
 }
 else
 {
  obj.style.display='block';
 }
}
window.onload=function()
{
 var olink=document.getElementById("link");
 var odiv=document.getElementById("thediv");
 olink.onclick=function()
 {
  Show_Hidden(odiv);
  return false;
 }
}
</script>
</head>
<body>
<a href="#" id="link">显示\隐藏切换</a>
<div id="thediv" style="display:block">本站欢迎您</div>
</body>
</html>