Question

我有以下嵌套数组products：

products: [
    [{
        Variant: {
            variant_id: '1',
            weight: 15
        },
        Product: {
            _id: '1',
            _shop_id: '1'
        },
        quantity: 5,
        totalPrice: 600
    }],
    [{
            Variant: {
                variant_id: '2',
                weight: 20
            },
            Product: {
                _id: '2',
                _shop_id: '2'
            },
            quantity: 4,
            totalPrice: 500
        },
        {
            Variant: {
                variant_id: '5',
                weight: 25
            },
            Product: {
                _id: '3',
                _shop_id: '2'
            },
            quantity: 3,
            totalPrice: 400
        }
    ]
]

我有一个packages数组，需要用package个对象填充。规则：包装中必须装有相同_shop_id的产品（明白了），并且产品总和不得超过30kg的极限重量。换句话说，如果Variant.weight的总和超过30，则需要添加一个新包。例如，products数组需要三个包：

// Package 1 - weight: 15kg - shopId: 1
{Variant: {variant_id: '1', weight: 15}, Product: {_id: '1', _shop_id:'1'}, quantity: 5, totalPrice: 600}

// Package 2 - weight: 20kg - shopId: 2
{Variant: {variant_id: '2', weight: 20}, Product: {_id: '2', _shop_id:'2'}, quantity: 4, totalPrice: 500}

// Package 3 - Needs new package because it would be 45kg - weight: 25kg - shopId: 2
{Variant: {variant_id: '5', weight: 25}, Product: {_id: '3', _shop_id:'2'}, quantity: 3, totalPrice: 400}

我只需要知道包装所有产品需要多少包装。 package对象将在一个软件包充满后添加，如下所示：

export interface Package {
    weight: number;
}

export class CartComponent {

  someMethod() { 
    let packages: Package[] = [];
    let weight = 0;

    products.forEach(prod =>
      {
          while(weight < 30) {
            weight += prod.Variant.weight;
            let package = { weight: weight };
          }
          packages.push(package);
      }
    });
  }

}

我做错了什么？我需要正确循环products数组以知道将使用多少个软件包。

Answer 1

请记住，您有一个数组数组。在外部阵列上调用forEach时，您会从一家商店获得内部产品阵列。然后，您必须以某种方式遍历内部数组。我建议使用forEach而不是while。以下几个简单的测试对我有用：

export class CartComponent {

  someMethod() { 
    let packages: Package[] = [];
    let weight = 0;
    let finishPackage = () => {
      packages.push({ weight: weight });
      weight = 0;
    };

    products.forEach(sameShopProducts =>
      {
        sameShopProducts.forEach(prod => {
          if (weight + prod.Variant.weight > 30) {
            finishPackage();
          }
          weight += prod.Variant.weight;
        });
        // Different shops cannot share a package.
        finishPackage();
      });
    return packages;
  }

}

如何在数组对象嵌套数组的条件下使用While循环？

1 个答案: