如何检查鼠标指针是否在另一个 div/id/a 中/上?
^a href="#" onmouseover="showmenu('top_3_menu_1_1')">Option One</a>
function showmenu(elmnt)
{
document.getElementById(elmnt).style.visibility="visible";
}
function hidemenu(elmnt)
{
if mouse pointer is not in location A or B do something
}