// JavaScript Document

/* + + + + + + + + + + + + + + + + + + +以下为Cookie操作部分 + + + + + + + + + + + + + + + + + + + + */
/**
++ update   : 2008-01-02
++ Author   : Rong
++ Name     : creatCookie
++ Function : 建立cookie
++ Param    : @string cookieName  : cookie名
              @string cookieValue : cookie值
			  @Number time        :cookie保存时间，单位:分钟
++ use      : creatCookie('menu_1','1',30) 
*/
function createCookie(cookieName, cookieValue, time){
	var expires = function(){ //Cookie保留时间
		var mydate = new Date();
		mydate.setTime(mydate.getTime + parseInt(time)*60*1000);
		return mydate.toGMTString();
	}
	document.cookie = cookieName + "=" + cookieValue + ";expires=" + expires + ";path=/";
}

/**
++ update   : 2008-01-02
++ Author   : Rong
++ Name     : getCookieValue
++ Function : 根据偏移量获得Cookie解码后的值
++ Param    : @string offset  : cookie偏移量
++ use      : getCookieValue(1) 
*/
function getCookieValue(offset) {
	var endstr = document.cookie.indexOf (";", offset);
	if (endstr == -1)
	endstr = document.cookie.length;
	return unescape(document.cookie.substring(offset, endstr));
}

/**
++ update   : 2008-01-02
++ Author   : Rong
++ Name     : getCookie
++ Function : 根据Cookie名获得Cookie解码后的值
++ Param    : @string cookieName  : cookie名
++ use      : getCookie('menu_1') 
*/
function getCookie(cookieName) {
	var arg = cookieName + "=";
	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 getCookieValue (j);
		i = document.cookie.indexOf(" ", i) + 1;
		if (i == 0) break;
	}
	return null;
}

/**
++ update   : 2007-12-28
++ Author   : Rong
++ Name     : delCookie
++ Function : 删除cookie
++ Param    : @string cookie cookieName  : cookie名
              @string cookie cookieValue : cookie值
++ use      : delCookie(cookieName,cookieValue)
*/
function delCookie(cookieName,cookieValue){
	document.cookie = cookieName + "=" + escape(cookieValue) + ";expires=Fri, 31 Dec 1999 23:59:59 GMT;path=/";
}

/* + + + + + + + + + + + + + + + + + + + Cookie操作部分结束 + + + + + + + + + + + + + + + + + + + + */