function swap_tab(n){ 
for(var i=1;i<=4;i++){ 
var curC=document.getElementById("tab_"+i); 
var curB=document.getElementById("tab_t"+i); 
if(n==i){ 
curC.style.display="block"; 
}else{ 
curC.style.display="none"; 
} 
} 
} 
//ÏÂÀ­²Ëµ¥

navHover = function() { 
var lis = document.getElementById("navmenu").getElementsByTagName("LI"); 
for (var i=0; i<lis.length; i++) { 
lis[i].onmouseover=function() { 
this.className+=" iehover"; 
} 
lis[i].onmouseout=function() { 
this.className=this.className.replace(new RegExp(" iehover\\b"), ""); 
} 
} 
} 
if (window.attachEvent) window.attachEvent("onload", navHover);