原生JS代码封装（添加cookie，获取cookie）

// 添加cookie

function addCookie(key,value,days) {

    var now = new Date();

    now.setDate(now.getDate() + days);

    document.cookie = key+"="+value+"; expires="+now;

}

// 获取cookie

function getCookie(key) {

    var str = document.cookie;

    if(!str) return null;

    

    var reg1 = new RegExp(key+"=([^;]+)$");

    var reg2 = new RegExp(key+"=([^;]+);");

    if(reg1.test(str)) {

        return str.match(reg1)[1];

    } else {

        return str.match(reg2)[1];

    }

}