30秒学会 JavaScript 片段 · 2019年1月14日

30秒学会 JavaScript 片段 – reducedFilter

Filter an array of objects based on a condition while also filtering out unspecified keys.

Use Array.prototype.filter() to filter the array based on the predicate fn so that it returns the objects for which the condition returned a truthy value.
On the filtered array, use Array.prototype.map() to return the new object using Array.prototype.reduce() to filter out the keys which were not supplied as the keys argument.

代码片段

const reducedFilter = (data, keys, fn) =>
  data.filter(fn).map(el =>
    keys.reduce((acc, key) => {
      acc[key] = el[key];
      return acc;
    }, {})
  );

使用样例

const data = [
  {
    id: 1,
    name: 'john',
    age: 24
  },
  {
    id: 2,
    name: 'mike',
    age: 50
  }
];

reducedFilter(data, ['id', 'name'], item => item.age > 24); // [{ id: 2, name: 'mike'}]