var objbak;
function menuOpreat(obj){
	var leftmen = document.getElementById("leftmenu");
	var tablerows = leftmen.rows.length;
	var bodyh = document.body.clientHeight;
	var menuh = 27;
	var modh = bodyh-tablerows*menuh-2;
	var trows = obj.parentNode.rowIndex;
	
	var o = leftmen.getElementsByTagName("ul"); 
	if(modh>0){
		for(i=0;i<o.length;i++){
			o[i].style.display = "none";
			o[trows].style.display = "block";
			o[trows].style.height = modh+'px';
			}
		}
		else{alert("你的窗口开得也太小了吧"); return true}
		objbak = obj;
	}
	
	
function Resize(){
	if(objbak){
		menuOpreat(objbak);
		}
	}