javascript - 迭代对象数组以合并新对象

Question

我正在尝试用数组创建新对象。我已经使用 lodash map 进行了尝试。但我的问题是如何获取特定集合中的 product_ids 并将其放入数组中。

这是对象

[
  [
    {
      "id": "b7079be6-c9ab-4d24-9a1d-38eddde926c2",
      "collection": "mortgages",
      "product_id": "854174665132787596022"
    },
    {
      "id": "0da12779-6fe9-45d5-afbf-91d2466e5b7e",
      "collection": "mortgages",
      "product_id": "304285269353822734222"
    },
    {
      "id": "87a137ba-5f66-4e94-8d5d-698dfbaa08ec",
      "collection": "mortgages",
      "product_id": "-304414504724243127922"
    }
  ],
  [
    {
      "id": "522f4b83-4c5a-4ffe-836d-33a51325d251",
      "collection": "carinsurance",
      "product_id": "10413803"
    },
    {
      "id": "02b79566-9cf7-48fa-a8d3-eecf951b5a76",
      "collection": "carinsurance",
      "product_id": "10397803"
    }
  ]
]

我已经试过这段代码了

map(this.products, (item, key) => {
   this.arr.push({
      collection: item[0].collection,
      product_ids: item.product_id
   });
});

我想要这样的结果。

{
    "collection": "mortgages",
    "product_ids": [
        "304285269353822734222",
        "854174665132787596022",
        "-304414504724243127922"
    ]
},
{
    "collection": "carinsurance",
    "product_ids": [
        "10413803",
        "10397803"
    ]
}

但我得到了这个结果。谁能帮我解决这个问题。

{
    "collection": "mortgages",
    "product_ids": undefined
},
{
    "collection": "carinsurance",
    "product_ids": undefined
}

Answer 1

item在你的情况下是一个数组，但你正在访问它，就好像有一个 product_id数组本身的字段，你必须映射所有 product_id数组中每个项目的属性:

map(this.products, (item, key) => {
   return {
      collection: item[0].collection,
      product_ids: item.map(i => i.product_id)
   };
});

此外，如果 map 函数返回一个数组，对于初始数组中的每个项目，它会将其转换为新格式，因此您可以返回并分配给 this.arr而不是推送到 this.arr在 map 函数中。