js按值从对象数组中删除重复项并计算重复项

Question

我有对象数组

const data=[
  {typeId: 1, sort: 1, name: "Test1"},
  {typeId: 2, sort: 1, name: "Test2"},
  {typeId: 1, sort: 2, name: "Test3"},
  {typeId: 3, sort: 1, name: "Test4"},
];

我想删除键“typeId”和键“sort”值更大的重复项。我想添加键“计数” - 对象按 typeId 重复的次数。

这就是我想要实现的：

const answer=[
  {typeId: 1, sort: 1, name: "Test1", count: 2},
  {typeId: 2, sort: 1, name: "Test2", count: 1},
  {typeId: 3, sort: 1, name: "Test4", count: 1},
];

我该怎么做？

Answer 1

您可以将对象按 typeId 分组并递增 count。

此方法假定 sort 的最小值始终为 1。

const 
    data = [{ typeId: 1, sort: 1, name: "Test1" }, { typeId: 2, sort: 1, name: "Test2" }, { typeId: 1, sort: 2, name: "Test3" }, { typeId: 3, sort: 1, name: "Test4" }],
    result = Object.values(data.reduce((r, o) => {
        if (r[o.typeId]) r[o.typeId].count++;
        else r[o.typeId] = { ...o, sort: 1, count: 1 };
        return r;
    }, {}));

console.log(result);

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Answer 2

此方法适用于 sort 的任何值。

const data = [
  {typeId: 1, sort: 1, name: "Test1"},
  {typeId: 2, sort: 1, name: "Test2"},
  {typeId: 1, sort: 2, name: "Test3"},
  {typeId: 3, sort: 1, name: "Test4"},
];

const answer = Object.values(data.reduce((p, v) => {
  const old = p[v.typeId];
  if (!old)
    p[v.typeId] = { ...v, count: 1 };
  else if (old.sort > v.sort)
    p[v.typeId] = { ...v, count: old.count + 1 };
  else
    p[v.typeId].count++;
  return p;
}, {}));

console.log(answer);

js按值从对象数组中删除重复项并计算重复项

js remove duplicate from array of objects by values and count duplicates

javascript

arrays

object

counting

duplicates