树的JS写法

<SCRIPT language=javascript1.2>
//展开或折叠树
function showTest(sid)
{
whichEl = eval("mytest" + sid);
if (whichEl.style.display == "none")
{
eval("mytest" + sid + ".style.display=\"\";");
}
else
{
eval("mytest" + sid + ".style.display=\"none\";");
}
}

//更换图标
function ToggleDisplay(oButton, oItems) {

 if (oItems.style.display == "none"){
  oItems.style.display = "";
  oButton.src = "images/minus.gif";
 } else {
  oItems.style.display = "none";
  oButton.src = "images/plus.gif";
 }

 return false;

}
</SCRIPT>


举例:<tr id=mytest1>要显示或隐藏的内容</tr>
<a onClick='showTest(1)'>显示</a>

eval()函数为执行命令
id.stytle.display ="none" 是隐藏
id.stytle.display='' 为显示