/*--------------------------------------------------------------------------
  -- 目的： 得到Cookie变量值
  -- 输入： 
  -- 返回： 
--------------------------------------------------------------------------*/ 
function GetCookie (name) {  
var arg = name + "=";  
var alen = arg.length;  
var clen = document.cookie.length;  
var i = 0;  
while (i < clen) {    
var j = i + alen;    
if (document.cookie.substring(i, j) == arg)      
return getCookieVal (j);    
i = document.cookie.indexOf(" ", i) + 1;    
if (i == 0) break;   
}  
return null;
}


/*--------------------------------------------------------------------------
  -- 目的： 设置Cookie变量值
  -- 输入： 
  -- 返回： 
--------------------------------------------------------------------------*/ 
function SetCookie (name, value) {  
var argv = SetCookie.arguments;  
var argc = SetCookie.arguments.length;  
var expires = (argc > 2) ? argv[2] : null;  
var path = (argc > 3) ? argv[3] : null;  
var domain = (argc > 4) ? argv[4] : null;  
var secure = (argc > 5) ? argv[5] : false;  
document.cookie = name + "=" + value + 
((expires == null) ? "" : ("; expires=" + expires.toGMTString())) + 
((path == null) ? "" : ("; path=" + path)) +  
((domain == null) ? "" : ("; domain=" + domain)) +    
((secure == true) ? "; secure" : "");
}


function getCookieVal(offset) {
var endstr = document.cookie.indexOf (";", offset);
if (endstr == -1)
endstr = document.cookie.length;
return document.cookie.substring(offset, endstr);
}