Javascript实现DIV的隐藏和出现

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />

<title>oec2003</title>

<script language="JavaScript" type="text/JavaScript">

<!--

function toggle(targetid){

    if (document.getElementById){

        target=document.getElementById(targetid);

            if (target.style.display=="block"){

                target.style.display="none";

            } else {

                target.style.display="block";

            }

    }

}

-->

</script>

<style type="text/css">

<!--

#div1{

background-color:#000000;

height:400px;

width:400px;

display:none;

}

-->

</style>

</head>

<body>

<input type="button" id="butn" value="显示/隐藏" onclick="toggle('div1')" />

<center>

<div id="div1"></div></center>

居中的DIV

</body>

</html>