JS 设置Cookie 有效期 检测cookie

function setCookie(name, value, days) { //设置cookie
     var d = new Date();
     d.setTime(d.getTime() + (days * 24 * 60 * 60 * 1000));
     var expires = "expires=" + d.toUTCString();
     document.cookie = name + "=" + value + "; " + expires;
    }

setCookie("key", 'value', 1);

document.cookie.indexOf("key")