javascript - 使用lodash groupBy函数对数组中的对象进行分类

Question

我有一个产品数组，每个产品都有一个类别对象。我需要按类别组织并包含类别对象。 GroupBy 函数仅包含一个参数。

产品系列

const data = [   
  {id: 1, 'name': 'produto1', category: {id: 1, name: 'shirts', description: 'super roupa'}},
  {id: 2, 'name': 'produto2', category: {id: 1, name: 'shirts', description: 'super roupa'}},
  {id: 3, 'name': 'produto3', category: {id: 2, name: 'jackets', description: 'super jackets'}},
  {id: 4, 'name': 'produto4', category: {id: 2, name: 'jackets', description: 'super jackets'}},    
]

预期结果:

[
  {
    category: {id: 1, name: 'clothes', description: 'super roupa'}, 
    products:[{id:1, name: 'produt1'}, {id: 2, name: 'produto1'} ]
  },
  {
    category: {id: 2, name: 'jackets', description: 'super jackets'}, 
    products:[{id:3, name: 'produt3'}, {id: 4, name: 'produto4'} ]
  },
]

Answer 1

按 category.id 进行分组，然后通过从组中第一项获取 category 并省略 将每个组映射到一个对象所有产品的类别:

const data = [{"id":1,"name":"produto1","category":{"id":1,"name":"shirts","description":"super roupa"}},{"id":2,"name":"produto2","category":{"id":1,"name":"shirts","description":"super roupa"}},{"id":3,"name":"produto3","category":{"id":2,"name":"jackets","description":"super jackets"}},{"id":4,"name":"produto4","category":{"id":2,"name":"jackets","description":"super jackets"}}]

const result = _(data)
  .groupBy('category.id')
  .map(group => ({
    category: _.head(group).category,
    products: _.map(group, o => _.omit(o, 'category'))
  }))
  .value()

console.log(result)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.js"></script>

或者与 lodash/fp 等效的 _.flow() 函数:

const { flow, groupBy, map, head, omit } = _

const fn = flow(
  groupBy('category.id'),
  map(group => ({
    category: head(group).category,
    products: map(omit('category'), group)
  }))
)

const data = [{"id":1,"name":"produto1","category":{"id":1,"name":"shirts","description":"super roupa"}},{"id":2,"name":"produto2","category":{"id":1,"name":"shirts","description":"super roupa"}},{"id":3,"name":"produto3","category":{"id":2,"name":"jackets","description":"super jackets"}},{"id":4,"name":"produto4","category":{"id":2,"name":"jackets","description":"super jackets"}}]

const result = fn(data)

console.log(result)

<script src='https://cdn.jsdelivr.net/g/lodash@4(lodash.min.js+lodash.fp.min.js)'></script>