javascript - 如何按照内部对象分配的方式连接数组？

Question

好吧，解释我想要什么有点困难。让我更详细地解释一下。我有一系列对象。因为数组元素的“唯一”标识符是它们的索引，所以如果我们想更改一个元素，我们需要知道哪个是目标索引。但即使我们有索引，我也不想更改整个对象，只需分配新对象并将它们“合并”在一起即可。

我有一个解决方案，虽然很丑陋，但至少更有意义我想要的:

const users = [
      {
        id: 0,
        name: "John",
        hobby: "soccer"
      },
      {
        id: 1,
        name: "Alice",
        hobby: "squash"
      },
      {
        id: 2,
        name: "Greg",
        hobby: "guitar"
      }
    ]

    const newUsers = [
      {
        id: 0,
        work: "developer"
      },
      {
        id: 2,
        work: "musician"
      },
      {
        id: 3,
        name: "Roger",
        work: "accountant"
      }
    ]

const concatArray = (newArray, oldArray) => {
  const objectFromArray = array => array.reduce((object, user) => {
    object[user.id] = user;
    return object
  }, {});

  const objectOfOldArray = objectFromArray(oldArray);
  const objectOfNewArray = objectFromArray(newArray);
  
  const allIds = Object.keys({...objectOfOldArray, ...objectOfNewArray})
  
  return allIds.map(id => {
    const oldProps = objectOfOldArray[id] || {};
    const newProps = objectOfNewArray[id] || {};
    return {id, ...oldProps, ...newProps}
  })
}

console.log(concatArray(newUsers, users))

它工作得很好，但应该有一个更充分的解决方案。我的意思是这是一个非常小的操作，向指定的对象添加一些属性，但我的解决方案过于复杂，无法实现这一点。应该有一种更简单的方法来赚取这个。

Answer 1

您可以尝试以下Array.forEach的方法

const users = [
      {
        id: 0,
        name: "John",
        hobby: "soccer"
      },
      {
        id: 1,
        name: "Alice",
        hobby: "squash"
      },
      {
        id: 2,
        name: "Greg",
        hobby: "guitar"
      }
    ]

const newUsers = [
  {
    id: 0,
    work: "developer"
  },
  {
    id: 2,
    work: "musician"
  },
  {
    id: 3,
    name: "Roger",
    work: "accountant"
  }
]

let updatedUsers = {};

[...users, ...newUsers].forEach(d => updatedUsers[d.id] = { ...(updatedUsers[d.id] || {}), ...d })

console.log(Object.values(updatedUsers))