javascript - 使用 Lodash 映射将列表重组为按值排序的键

Question

如果不遍历数组 3 次，我不知道该怎么做。

我希望转换一组如下所示的职位列表:

const jobs = [
  {
    title: 'Manager',
    department: 'Retail',
    location: 'New York'
  },
  {
    title: 'Customer Service Rep',
    department: 'Corporate',
    location: 'Washington D.C.'
  },
  {
    title: 'Clerk',
    department: 'Retail',
    location: 'New York'
  },
  ...
];

进入具有相关工作的独特部门的对象:

const deps = {
  'Corporate': [
    {
      title: 'Customer Service Rep',
      department: 'Corporate',
      location: 'Washington D.C.'
    },
  ],
  'Retail': [
    {
      title: 'Manager',
      department: 'Retail',
      location: 'New York'
    },
    {
      title: 'Clerk',
      department: 'Retail',
      location: 'New York'
    },
  ],
};

_map 是我最好的选择吗？有没有更 Eloquent 方式来做到这一点？

Answer 1

您可以使用array#reduce 根据部门 对作业进行分组。

const jobs = [ { title: 'Manager', department: 'Retail', location: 'New York' }, { title: 'Customer Service Rep', department: 'Corporate', location: 'Washington D.C.' }, { title: 'Clerk', department: 'Retail', location: 'New York' }],
    deps = jobs.reduce((r,job) => {
      r[job.department] = r[job.department] || [];
      r[job.department].push(job);
      return r;
    },{});
console.log(deps);

您可以使用 _.groupBy

const jobs = [ { title: 'Manager', department: 'Retail', location: 'New York' }, { title: 'Customer Service Rep', department: 'Corporate', location: 'Washington D.C.' }, { title: 'Clerk', department: 'Retail', location: 'New York' }],
    deps = _.groupBy(jobs, 'department');
console.log(deps);

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