//两个参数，一个是cookie的名子，一个是值
function SetCookie(name,value,path)
{
    var Days = 365; //此 cookie 将被保存 365 天
    var exp  = new Date();    //new Date("December 31, 9998");
    exp.setTime(exp.getTime() + Days*24*60*60*1000);
    var strValue=name + "="+ escape (value) + ";expires=" + exp.toGMTString();
    if(path!=null && path!=undefined)strValue+=";path=" + path;
    document.cookie = strValue;
}
//四个参数：name为cookie名称，value为cookie值，path为cookie生成的网页目录［相对路径］,day为保存的天数
function setCookieDays(name,value,path,day)
{
	var exp  = new Date();
    exp.setTime(exp.getTime() + parseInt(day)*24*60*60*1000);
    var strValue=name + "="+ escape (value) + ";expires=" + exp.toGMTString();
    if(path!=null && path!=undefined)strValue+=";path=" + path;
    document.cookie = strValue;
}

function getCookie(name)//取cookies函数        
{
    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
     if(arr != null) return unescape(arr[2]); return null;

}

function delCookie(name)//删除cookie
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    alert(name + "="+cval+";expires="+exp.toGMTString());
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}

function delCookieRoot(name)//删除cookie,当前路径不为根路径,而cookie目录为根时
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString()+";path=/";
}