Javascript 获取方法（对象）外部的变量

我希望在方法之外检索变量，但OOP对我来说是新事物，我有点卡住了

const Reservation = {
    play: document.getElementById('Reservation'),
    reset: document.getElementById('annuler'),

    launch_functions_sessionStorage: function () {
        this.onReservation();
        this.displayIfChecked();
        this.set_Timer();
    },

    displayIfChecked: function () {
        SOMETHING
    },

    onReservation: function () {
        $('#Reservation, .signature',).click(function () {
            console.log();
            if (SOMETHING) {
                let checked = 1;
            } else {
                let checked = 0;
            }
        });
    },

    set_Timer: function () {

        Reservation.play.addEventListener('click', function(){
            if('I would like to get 'checked'){}
        });
    }
};
Reservation.launch_functions_sessionStorage();

我试图保留重要信息以供您理解。 同时为我的英语感到抱歉。。。

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非常感谢

这就是您要找的吗

const Reservation = {
    play: document.getElementById('Reservation'),
    reset: document.getElementById('annuler'),

    launch_functions_sessionStorage: function () {
        this.onReservation();
        this.displayIfChecked();
        this.set_Timer();
    },

    displayIfChecked: function () {
        SOMETHING
    },

    onReservation: function () {
        $('#Reservation, .signature',).click(function () {
            console.log();
            if (SOMETHING) {
                let checked = 1;
            } else {
                let checked = 0;
            }
        });
    },
    varThatCanBeCheckedInSetTimer : false,
    set_Timer: function () {
        Reservation.play.addEventListener('click', function(){
            if(varThatCanBeCheckedInSetTimer){
                //your stuff that will happen only if you set varThatCanBeCheckedInSetTimer  to true
             }
        });
    }
};

你会像这样使用它

Reservation.varThatCanBeCheckedInSetTimer = true;
Reservation.set_Timer();

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问题出在哪里？如何通过将变量作为参数传递来检查set_timer:function上的变量？我不确定我是否理解这里的问题。我想它可以解决我的问题。同时，我不知道如何在方法之外调用变量。只是^^^类似于

预订。设置时间（参数…

？@LudovicWEBER很乐意帮忙，回答问题并+1被认为是很好的；）