function switchmenu(obj)...{ if(document.getElementById)...{ var el = document.getElementById(obj); var ar = document.getElementById("maindiv").getElementsByTagName("span"); if(el.style.display !="block")...{ for (var i=0; i<ar.length; i++)...{ if (ar[i].className=="submenu") ar[i].style.display ="none"; } el.style.display ="block"; }else...{ el.style.display ="none"; } } }