//swap_tab(n,k,m) n为当前ID,k为TAB个数 m为tab的编号
function swap_tab(n,k,m){
	for(var i=1;i<=k;i++){
		var curC=document.getElementById("tab"+m+"_"+i);
		var curB=document.getElementById("tab"+m+"_t"+i);
		if(n==i){
			curC.style.display="block";
			curB.className="active"
		}else{
			curC.style.display="none";
			curB.className="normal"
		}
	}
} 
//<li class="active" id="tab5_t1" onmouseover="return swap_tab(1,4,5)" ></li>
//<li class="normal" id="tab5_t2" onmouseover="return swap_tab(2,4,5)" ></li>
//<ul id="tab5_1" ></ul>
//<ul id="tab5_2" ></ul>