映射两个数组

Question

我有两个数组。

let A = [{
  "id": 22,
  "name": "ABC",
  "createdDate": "2021-04-19T05:55:41.247+0000",
  "modifiedDate": null
}, {
  "id": 23,
  "name": "DEF",
  "createdDate": "2021-04-19T05:55:41.247+0000",
  "modifiedDate": null
}, {
  "id": 24,
  "name": "GHI",
  "createdDate": "2021-04-19T05:55:41.247+0000",
  "modifiedDate": null
}]

let B = [{
  "key": "selectedId",
  "value": "id"
}, {
  "key": "selectedName",
  "value": "name"
}]

我想映射这两个数组。就像下面的数组一样。

let C = [{
  selectedId: 22,
  selectedName: "ABC"
}, {
  selectedId: 23,
  selectedName: "DEF"
}, {
  selectedId: 24,
  selectedName: "GHI"
}]

下面显示了我尝试过的内容，所以 far.I 不知道如何像上面的数组一样映射数据。如果有人能回答这个问题，那将是一个巨大的帮助。

A.forEach(item => {
   B.forEach(element => {
             
   });
});

Answer 1

您可以将条目映射到想要的 key/value 对。

const
    data = [{ id: 22, name: "ABC", createdDate: "2021-04-19T05:55:41.247+0000", modifiedDate: null }, { id: 23, name: "DEF", createdDate: "2021-04-19T05:55:41.247+0000", modifiedDate: null }, { id: 24, name: "GHI", createdDate: "2021-04-19T05:55:41.247+0000", modifiedDate: null}],
    keys = [{ key: "selectedId", value: "id" }, { key: "selectedName", value: "name" }],
    result = data.map(o =>
        Object.fromEntries(keys.map(({ key, value }) => [key, o[value]]))
    );

console.log(result);

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Answer 2

const 
  A = [
    {"id":22,"name":"ABC","createdDate":"2021-04-19T05:55:41.247+0000","modifiedDate":null},
    {"id":23,"name":"DEF","createdDate":"2021-04-19T05:55:41.247+0000","modifiedDate":null},
    {"id":24,"name":"GHI","createdDate":"2021-04-19T05:55:41.247+0000","modifiedDate":null}
  ],
  B = [
    {"key":"selectedId","value":"id"},
    {"key":"selectedName","value":"name"}
  ];

// get map of prop-key from B
const map = B.reduce((map, {key,value}) => map.set(value, key), new Map);

// iterate over A
const res = A.map(item => 
  // from the current item, construct an object using the above map
  [...map.entries()].reduce((obj, [prop, key]) => ({...obj, [key]: item[prop]}), {})
);

console.log(res);

Answer 3

您正在将一个数组转换为另一个长度相同的数组，所以是的 - 这是一个映射操作。在其中，您正在将数组转换为……其他东西。这是一个减少。

这是我的方法：

let A = [
  {
    id: 22,
    name: "ABC",
    createdDate: "2021-04-19T05:55:41.247+0000",
    modifiedDate: null,
  },
  {
    id: 23,
    name: "DEF",
    createdDate: "2021-04-19T05:55:41.247+0000",
    modifiedDate: null,
  },
  {
    id: 24,
    name: "GHI",
    createdDate: "2021-04-19T05:55:41.247+0000",
    modifiedDate: null,
  },
];

let B = [
  {
    key: "selectedId",
    value: "id",
  },
  {
    key: "selectedName",
    value: "name",
  },
];

const output = A.map((item) =>
  B.reduce((accum, pair) => ({ ...accum, [pair.key]: item[pair.value] }), {})
);

console.log(output);

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