点击按钮展开列表，再次点击收回列表

<script type="text/javascript">
function ClickMenu(diving) {
	//alert(diving);
	if (document.getElementById(diving).style.display == "none") {
		document.getElementById(diving).style.display = 'block';
	}
	else {
		document.getElementById(diving).style.display = 'none';
	}
}
</script>
<div class='banner2'><img src='images/plus.gif' height='15' width='15' border='0' alt='' /><a onclick=ClickMenu('TreeNode0')>分行管理</a></div>
<div id='TreeNode0' class='bannermid' style='display:none'>
	"echo"
	<div class='banner3'><img src='images/erji1.jpg' height='20' width='36' border='0' alt='' /> <a href='media.php' target='Right'>宣传片</a></div>
	<div class='banner3'><img src='images/erji1.jpg' height='20' width='36' border='0' alt='' /> <a href='picture.php' target='Right'>海报</a></div>
</div>

　　

参考链接：https://zhidao.baidu.com/question/490209679.html