最近项目写了一些js，水平有待提高

function ResumeError() { 
return true; 
} 
window.onerror = ResumeError; function showdd(obj){ 
var dds = document.getElementById(obj).getElementsByTagName("dd"); 
var len = dds.length; 
if(dds[0].style.display == "none"){ 
//该操作为展开菜单，需要判断cookie中是否有该项 
//1、有，删除 
//2、无，不执行操作 
changeshowmenu(obj); 
for(var i = 0; i < len;i++){ 
dds[i].style.display = ""; 
} 
}else{ 
//该操作为隐藏菜单，需要判断cookie中是否有该项： 
//1、有，不执行操作 
//2、无，则要在末尾添加进去 
changehidemenu(obj); 
for(var i = 0; i < len;i++){ 
dds[i].style.display = "none"; 
} 
} 
} 
function changeshowmenu(obj){ 
var temp = getcookie("openid"); 
if(temp.indexOf(obj) != "-1"){ 
temp = temp.replace(obj + ",","") 
addcookie("openid",temp,24); 
} 
} 
function changehidemenu(obj){ 
var temp = getcookie("openid"); 
if(temp.indexOf(obj) == "-1"){ 
addcookie("openid",temp+obj+",",24); 
} 
} 

function getcookie(sName) {//取得cookie 
var aCookie = document.cookie.split("; "); 
for (var j=0; j < aCookie.length; j++){ 
var aCrumb = aCookie[j].split("="); 
if (sName == aCrumb[0]) 
return aCrumb[1]; 
} 
return null; 
} 
function addcookie(objName,objValue,objHours){//添加cookie 
var str = objName + "=" + objValue; 
if(objHours > 0){//为0时不设定过期时间，浏览器关闭时cookie自动消失 
var date = new Date(); 
var ms = objHours*3600*1000; 
date.setTime(date.getTime() + ms); 
str += "; expires=" + date.toGMTString(); 
} 
document.cookie = str; 
} 
//根据一个以逗号分开的字符串，初始化菜单哪些需要隐藏 
function initmenu(obj){ 
var arrmenu = obj.split(","); 
for(var i = 0; i < arrmenu.length;i++){ 
var dds = document.getElementById(arrmenu[i]).getElementsByTagName("dd"); 
for(var j = 0;j < dds.length;j++){ 
dds[j].style.display = "none"; 
} 
} 
} 
function $(obj){ 
return document.getElementById(obj); 
} 
function delIt(){ 
var cbxBool = 0; 
for(var i = 0;i < cbxArray.length;i++){ 
var obj = $(cbxArray[i]); 
if(obj.checked == true){ 
cbxBool = 1; 
break; 
} 
} 
if(cbxBool == 1){ 
var result = confirm("操作不可以恢复，确定当前操作吗？"); 
if(result){ 
return true; 
} 
}else{ 
alert("您还没有选中项"); 
return false; 
} 
return false; 
} 
window.onload = function(){ 
var lendl = document.getElementById("globalLeft").getElementsByTagName("dl").length; 
if(getcookie("openid") == null){ 
addcookie("openid","dl_c,dl_d,dl_e,dl_f,dl_g,dl_h,dl_i,dl_j,",24); 
} 
initmenu(getcookie("openid")); 

var otable = document.getElementById("table"); 
var trs = otable.getElementsByTagName("tr"); 
for(var i = 0;i < trs.length;i++){ 
trs[i].onmouseover = function(){ 
this.style.backgroundColor = "#F7F7F7"; 
} 
trs[i].onmouseout = function(){ 
this.style.backgroundColor = "#FFFFFF"; 
} 
} 
}