如何从重复数组中创建一个数组并将其合并？

Question

myArra.js

[
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028567b45073399077becf",
    "slno": "A2",
    "checkPoint": "Flush height of Adaptor CAT position",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "NO",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028572b45073399077bed1",
    "slno": "A3",
    "checkPoint": "Position of CAT bottom side",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "6102857fb45073399077bed3",
    "slno": "A4",
    "checkPoint": "Flush height of  CAT bottom side",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "6102858cb45073399077bed5",
    "slno": "B1",
    "checkPoint": "Position of Front cap pipe outer",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  }
]

在上面的代码中，我有一个对象数组，它有重复的元素。例如，它具有对象元素，例如 'slno'、'checkPoint' 和 'id' 是相同的。所以所有这些重复的对象应该只成为一个对象，而且每个对象中的元素“va”是一个数组，它在每个重复对象中都具有相同的长度。在这些重复的对象中，它也应该成为一个数组，如果数组有值，则应该填充空索引。 所以，结果应该类似于

结果

[
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      "YES",
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028567b45073399077becf",
    "slno": "A2",
    "checkPoint": "Flush height of Adaptor CAT position",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "NO",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028572b45073399077bed1",
    "slno": "A3",
    "checkPoint": "Position of CAT bottom side",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "6102857fb45073399077bed3",
    "slno": "A4",
    "checkPoint": "Flush height of  CAT bottom side",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "6102858cb45073399077bed5",
    "slno": "B1",
    "checkPoint": "Position of Front cap pipe outer",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  }
]

所以在 myArray.js 中有 3 个具有相同 id、slno 和 checkPoint 的重复项。所以结果它变成了只有一个元素。但是，数组“va”在每个元素中都不同。即 19、22 和 23 指数。所以它变成了一个数组，并为各个索引分配了各自的值，其余的值除了第 19,22 和 23 索引变为空。

Answer 1

应该这样做。

let a = [
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028558b45073399077becd",
    "slno": "A1",
    "checkPoint": "Position of adaptor CAT",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "YES",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028567b45073399077becf",
    "slno": "A2",
    "checkPoint": "Flush height of Adaptor CAT position",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      "NO",
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "61028572b45073399077bed1",
    "slno": "A3",
    "checkPoint": "Position of CAT bottom side",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "6102857fb45073399077bed3",
    "slno": "A4",
    "checkPoint": "Flush height of  CAT bottom side",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  },
  {
    "id": "6102858cb45073399077bed5",
    "slno": "B1",
    "checkPoint": "Position of Front cap pipe outer",
    "va": [
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null,
      null
    ]
  }
];

let filtered = {};

a.forEach(v => {
  if (filtered[v.id]) {
    filtered[v.id].va = filtered[v.id].va.map((subvalue, position) => {
      return (subvalue || v.va[position]);
    });
  } else {
    filtered[v.id] = v;
  }
});

console.log(Object.entries(filtered));