lodash 唯一基于除属性之外的所有内容答案

【问题标题】：lodash unique based on everything except attributelodash 唯一基于除属性之外的所有内容
【发布时间】：2022-01-22 03:31:50
【问题描述】：

这与lodash unique based on attribute 的要求相反，这里我想通过忽略一个（或多个）属性来使数组唯一。

所以在下面，我不关心“年龄”属性（可能有多个记录，我只想保留细节变化的地方）。

const arr = [{
  "id": 1,
  "name": "Jen",
  "age": 31,
  "eyecolor": "blue",
  "hair": "brown",
}, {
  "id": 1,
  "name": "Jen",
  "age": 32,
  "eyecolor": "blue",
  "hair": "brown"
}, {
  "id": 2,
  "name": "Jules",
  "age": 31,
  "eyecolor": "blue",
  "hair": "brown"
}, {
  "id": 2 "name": "Brian",
  "age": 40,
  "eyecolor": "blue",
  "hair": "brown"
}];

const unique = _.uniqBy(arr, 'id');

console.log(unique);

// const uniqueNot = _.uniqExcept(arr, 'age');
// keeps one of the Jen objects, but both of the Jules/Brian objects

&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"&gt;&lt;/script&gt;

正如评论所说，我希望以上内容保留 Jen 对象之一，但同时保留 Jules/Brian 对象。

我想我可以这样做：

const arr = [{
  "id": 1,
  "name": "Jen",
  "age": 31,
  "eyecolor": "blue",
  "hair": "brown",
}, {
  "id": 1,
  "name": "Jen",
  "age": 32,
  "eyecolor": "blue",
  "hair": "brown"
}, {
  "id": 2,
  "name": "Jules",
  "age": 31,
  "eyecolor": "blue",
  "hair": "brown"
}, {
  "id": 2,
  "name": "Brian",
  "age": 40,
  "eyecolor": "blue",
  "hair": "brown"
}];

const omissionComparator = (withoutKeys) => (a, b) => _.isEqual(_.omit(a, withoutKeys), _.omit(b, withoutKeys))

const  uniqueWithoutAge = _.uniqWith(_.orderBy(arr, ['id','age'], ['asc', 'desc']), omissionComparator('age'));

console.log(uniqueWithoutAge);

&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"&gt;&lt;/script&gt;

但是有没有办法在没有自定义比较器和/或必须先对数组进行排序的情况下做到这一点？

【问题讨论】：

我不清楚您为什么将排序作为此操作的一部分。结果是一样的，afaic。 orderBy 似乎没有必要。
@kaliatech 保留了年龄为 31 的未排序 Jen，保留了年龄为 32 的排序 Jen。此外，按 ID 排序会保留原始顺序（但不一定总是如此）

标签： javascript lodash unique

【解决方案1】：

也许是这个？ uniqBy + omit + JSON.stringify

const arr = [{
  "id": 1,
  "name": "Jen",
  "age": 31,
  "eyecolor": "blue",
  "hair": "brown",
}, {
  "id": 1,
  "name": "Jen",
  "age": 32,
  "eyecolor": "blue",
  "hair": "brown"
}, {
  "id": 2,
  "name": "Jules",
  "age": 31,
  "eyecolor": "blue",
  "hair": "brown"
}, {
  "id": 2,
  "name": "Brian",
  "age": 40,
  "eyecolor": "blue",
  "hair": "brown"
}];

const keysToIgore = ['age'];

const result = _.uniqBy(arr, o => JSON.stringify(_.omit(o, keysToIgore)));
console.log(result);

&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.js"&gt;&lt;/script&gt;

【讨论】：