如何在嵌套的物件陣列中找到索引？

我有一個嵌套的物件陣列，dishes其中包含唯一的 ID。如果id存在于foodItems中dishes，我想找到陣列的索引，然后將其從中洗掉foodItems

const dishes = [{
        cuisine: 'Chinese',
        foodItems: [{
                id: '1',
                dishName: 'Chicken noodles',
                price: '6.00 USD'
            },
            {
                id: '2',
                dishName: 'Fried rice',
                price: '5.00 USD'
            },
            {
                id: '3',
                dishName: 'Dumplings',
                price: '2.00 USD'
            }
        ],
    },
    {
        cuisine: 'Indian',
        foodItems: [{
                id: '4',
                dishName: 'Tikka masala',
                price: '10.00 USD'
            },
            {
                id: '5',
                dishName: 'Naan Bread',
                price: '2.00 USD'
            },
            {
                id: '6',
                dishName: 'Dal Fry',
                price: '4.00 USD'
            }
        ],
    }
];

在這里，是我試了一下（這是不作業，回傳undefined的index）：

let removeId = (id) => {
    let index = dishes.forEach(dish => dish.foodItems.findIndex(item => item.id === id)); // returns undefined
    if (index !== -1) {
        dishes.forEach(dish=> dish.foodItems.splice(index, 1)); // remove obj from foodItems array
        return true;
    } else {
        return false;
    }
}

uj5u.com熱心網友回復：

您需要在forEach()回呼方法中包含其余邏輯。但是，考慮到您希望true在洗掉專案后回傳，使用for ... of回圈更容易：

const dishes = [{
    cuisine: 'Chinese',
    foodItems: [{
        id: '1',
        dishName: 'Chicken noodles',
        price: '6.00 USD'
      },
      {
        id: '2',
        dishName: 'Fried rice',
        price: '5.00 USD'
      },
      {
        id: '3',
        dishName: 'Dumplings',
        price: '2.00 USD'
      }
    ],
  },
  {
    cuisine: 'Indian',
    foodItems: [{
        id: '4',
        dishName: 'Tikka masala',
        price: '10.00 USD'
      },
      {
        id: '5',
        dishName: 'Naan Bread',
        price: '2.00 USD'
      },
      {
        id: '6',
        dishName: 'Dal Fry',
        price: '4.00 USD'
      }
    ],
  }
];

const removeId = (id) => {
    for (let dish of dishes) {
        const index = dish.foodItems.findIndex(fi => fi.id === id);
        if (index > -1) {
          dish.foodItems.splice(index, 1);
          return true;
        }
    };
    return false;
}

console.log(removeId('1'));
console.log(removeId('4'));
console.log(removeId('7'));

console.log(dishes);

uj5u.com熱心網友回復：

你可以試試這個，使用 for of 并添加條目變數你 for 回圈

const dishes = [
  {
    cuisine: "Chinese",
    foodItems: [
      {
        id: "1",
        dishName: "Chicken noodles",
        price: "6.00 USD",
      },
      {
        id: "2",
        dishName: "Fried rice",
        price: "5.00 USD",
      },
      {
        id: "3",
        dishName: "Dumplings",
        price: "2.00 USD",
      },
    ],
  },
  {
    cuisine: "Indian",
    foodItems: [
      {
        id: "4",
        dishName: "Tikka masala",
        price: "10.00 USD",
      },
      {
        id: "5",
        dishName: "Naan Bread",
        price: "2.00 USD",
      },
      {
        id: "6",
        dishName: "Dal Fry",
        price: "4.00 USD",
      },
    ],
  },
];

for (const [idx, items] of dishes.entries()) {
  console.log(items.foodItems)
}

對于此處的檔案：https : //developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of

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