javascript cookie类(删除cookie，获取,设置cookie值

function issetcookie(){//网页特效检查cookie的函数
    bannercenter = 网页特效getcookie('bannercenter');
    if (bannercenter!=null && bannercenter!=""){
        return true;
    } else {
        setcookie('bannercenter',1,3600*24);
    }
}

//===============================================
function jsgetcookie(name){//获得cookie的原始值
    var cookstringarray    = window.document.cookie.split("; ");
    for(var i=0; i<cookstringarray.length;i++){     
        var cookieinfo = cookstringarray[i].split("=");
        if(name == cookieinfo[0]) {
            return unescape(cookieinfo[1]);
        }      
      }
    return null;
}

function setcookie(name, value){//设定cookie值
    var expdate = new date();
    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;
    if(expires!=null) expdate.settime(expdate.gettime() + ( expires * 1000 ));
        document.cookie = name + "=" + escape (value) +((expires == null) ? "" : ("; expires="+ expdate.togmtstring()))
        +((path == null) ? "" : ("; path=" + path)) +((domain == null) ? "" : ("; domain=" + domain))
        +((secure == true) ? "; secure" : "");
    }
//=============================================
function delcookie(name){//删除cookie
    var exp = new date();
    exp.settime (exp.gettime() - 1);
    var cval = getcookie (name);
    document.cookie = name + "=" + cval + "; expires="+ exp.togmtstring();

}