javascript - 如何从数组中获取最后一个对象并在javascript中保持父数组相同

Question

嗨，我有一个带有消息键的数组，其中有多个对象，我想删除消息数组中除最后一个对象之外的所有对象

我有下面的示例数组:

const array = [
    {
      messages: [
        { content: "abc", id: "message01" },
        { content: "def", id: "message02" },
        { content: "ghi", id: "message03" }
      ],
      user: "user 1",
      participants: ["user1", "user2"],
      id: "chat01"
    },
    {
      messages: [
        { content: "hello", id: "message01" },
        { content: "hi", id: "message02" },
        { content: "How are you", id: "message03" }
      ],
      user: "user 2",
      participants: ["user1", "user2"],
      id: "chat02"
    }
  ];

下面是我的异常(exception)数组:

const expectedArray = [
    {
      messages: [{ content: "ghi", id: "message03" }],
      user: "user 1",
      participants: ["user1", "user2"],
      id: "chat01"
    },
    {
      messages: [{ content: "How are you", id: "message03" }],
      user: "user 2",
      participants: ["user1", "user2"],
      id: "chat02"
    }
  ];

Answer 1

这是你想要的吗？

编辑:此代码将循环数组，并将 messages 设置为 messages[0] 这是最后一个对象

const array = [
  {
    messages: [
      {
        content: "abc",
        id: "message01"
      },
      {
        content: "def",
        id: "message02"
      },
      {
        content: "ghi",
        id: "message03"
      }
    ],
    user: "user 1",
    participants: ["user1", "user2"],
    id: "chat01"
  },
  {
    messages: [
      {
        content: "hello",
        id: "message01"
      },
      {
        content: "hi",
        id: "message02"
      },
      {
        content: "How are you",
        id: "message03"
      }
    ],
    user: "user 2",
    participants: ["user1", "user2"],
    id: "chat02"
  }
];

array.forEach(e=>{
  e.messages = e.messages[e.messages.length - 1]
})

console.log(array)