JS循环中遍历目标数组实现4周餐单随机洗牌展示

你的现有逻辑已经完成了单数组打乱、每日特餐输出的核心功能，只需要调整数组取值逻辑，就能实现4周分别对应4个不同餐单数组的需求，不需要改动已写好的menu对象、shuffle打乱函数。

具体修改点 #

• 在所有餐单数组（meals/meals1/meals2/meals3）定义完成后，新增一个按周顺序存储餐单的数组：

// 索引0对应第1周餐单，索引3对应第4周餐单
const weeklyMealLists = [meals, meals1, meals2, meals3];

• 替换原有的周循环逻辑：不再固定操作meals数组，每次周循环根据索引取对应周的餐单，打乱后输出即可。同时把原在内层循环的数组长度校验移到外层，减少冗余判断。

修改后可直接运行的完整代码 #

const menu = {
    _meal: "",
    _price: 0,
    // 仅当传入值为字符串时更新餐品名称
    set meal(mealToCheck) {
        if (typeof mealToCheck === "string") {
            return (this._meal = mealToCheck);
        }
    },
    // 仅当传入值为数字时更新餐品价格
    set price(priceToCheck) {
        if (typeof priceToCheck === "number") {
            return (this._price = priceToCheck);
        }
    },
    // 餐品和价格都合法时返回特餐文案，否则返回错误提示
    get todaysSpecial() {
        if (this._meal && this._price) {
            return `'s Special is ${this._meal}, for just ${this._price}£!!`;
        } else {
            return "Meal and Price wasn't entered correctly!!";
        }
    }
};

// 各周餐品及对应价格数组
let meals = [
    {name: "Pizza", price: 9},
    {name: "Steak", price: 13},
    {name: "Pie", price: 11},
    {name: "Roast", price: 14},
    {name: "Moussaka", price: 9},
    {name: "Lasagne", price: 10},
    {name: "Tacos", price: 9}
];
let meals1 = [
    {name: "Omelette", price: 9},
    {name: "Kebab", price: 13},
    {name: "Ratatouille", price: 14},
    {name: "Quiche", price: 9},
    {name: "Burgers", price: 9},
    {name: "Hot-Dogs", price: 10},
    {name: "Burritos", price: 9}
];
let meals2 = [
    {name: "Bourguignon", price: 10},
    {name: "Stew", price: 14},
    {name: "Fish&Chips", price: 15},
    {name: "Fried Chicken", price: 10},
    {name: "Cannelloni", price: 10},
    {name: "Crepes", price: 11},
    {name: "Gyros", price: 10}
];
let meals3 = [
    {name: "Greek Salad", price: 11},
    {name: "Seafood", price: 15},
    {name: "Falafel", price: 16},
    {name: "Wraps", price: 11},
    {name: "Souvlaki", price: 11},
    {name: "Shawarma", price: 12},
    {name: "Quesadilla", price: 11}
]

// 按周顺序存储餐单的容器
const weeklyMealLists = [meals, meals1, meals2, meals3];

// 数组随机打乱函数
const shuffle = (array) => {
    let currentIndex = array.length,
        randomIndex;
    while (currentIndex !== 0) {
        randomIndex = Math.floor(Math.random() * currentIndex);
        currentIndex--;
        [array[currentIndex], array[randomIndex]] = [
            array[randomIndex],
            array[currentIndex]
        ];
    }
    return array;
}

let week = ["Week 1", "Week 2", "Week 3", "Week 4"];
const dayOfTheWeek = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"]

// 周循环输出餐单
for (let w = 0; w < week.length; w++) {
    console.log("\n" + week[w])
    // 对当前周的餐单做浅拷贝后打乱，避免修改原始数组数据
    const currentWeekMeals = shuffle([...weeklyMealLists[w]]);
    // 提前校验餐品数量和一周天数是否匹配
    if (currentWeekMeals.length !== dayOfTheWeek.length) {
        const diff = Math.abs(currentWeekMeals.length - dayOfTheWeek.length);
        if (currentWeekMeals.length < dayOfTheWeek.length) {
            console.log(`You need to add ${diff} meal(s) to the list!!!`)
        } else {
            console.log(`You need to remove ${diff} meal(s) from the list!!!`)
        }
        continue;
    }
    // 遍历输出每日特餐
    for (let i = 0; i < currentWeekMeals.length; i++) {
        menu.meal = currentWeekMeals[i].name;
        menu.price = currentWeekMeals[i].price;
        console.log(dayOfTheWeek[i] + menu.todaysSpecial);
    }
}

补充说明 #

• 代码里用[...weeklyMealLists[w]]做浅拷贝，是为了避免打乱操作修改最开始定义的原始餐单数组，每次运行代码都能得到基于原始餐单的全新随机结果
• 把长度校验移出天循环后，避免了重复判断，执行逻辑更顺畅

内容的提问来源于stack exchange，提问作者Giovanni Farina