javascript - 按 Id 对数组中的对象进行分组 - JavaScript

Question

我有一个对象数组，它有两个字段 id 和操作权限的类型

const array=[
{view: false, id: 1},
{create: false, id: 1},
{read: false, id: 1},
{update: false, id: 1},
{delete: false, id: 1},
{view: false, id: 2},
{create: false, id: 2},
{read: false, id: 2},
{update: false, id: 2},
{delete: false, id: 2},
]

我想将其转换为以下数组:

const permissions=[
{
id: 1,
view: false,
read: false,
create: false,
delete:false,
update:false
},
{
id: 2,
view: false,
read: false,
create: false,
delete:false,
update:false
}
]

Answer 1

您可以使用 Array#reduce 遍历数组在更新 Map 时其中 id 是 key，其结果对象是 value。

最后，您会将每个 id 的分组对象作为此映射中的 values:

const array = [
  {view: false, id: 1},
  {create: false, id: 1},
  {read: false, id: 1},
  {update: false, id: 1},
  {delete: false, id: 1},
  {view: false, id: 2},
  {create: false, id: 2},
  {read: false, id: 2},
  {update: false, id: 2},
  {delete: false, id: 2},
];

const res = [...
  array.reduce((map, { id, ...elem }) =>
    map.set(id, { ...(map.get(id) || { id }), ...elem })
  , new Map)
  .values()
];

console.log(res);