如何在使用 axios 获取的数组上进行 map

Question

I am working on a chat-app and is trying to make a fetch using axios for the first time. I have succeded in making the fetch because I see the array from the url when I console.logging it. However I want to map over all the messages in the array and display them for a user. But I am doing something wrong so the mapping dosent work. Can someone help me to see why?

This is my code (I belive that its the map-function that is creating the problem):

import React, { useState, useEffect } from 'react'
import { BrowserRouter, Switch, Route } from 'react-router-dom'
import axios from 'axios'


export const GetMessages = () => {
  const [userName, setUserName] = useState([]);
  const [userMessage, setUserMessage] = useState([]);

  const fetchResponse = async () => {
    try {
      const getResponse = await axios.get(
      'http://167.172.108.61/?storage=camilla_lofroth'
    )
    console.log(getResponse)
    setUserMessage(getResponse)
    } catch (error) {
      alert('Error')
    }
    return[]
  }  

  useEffect(() => {
    fetchResponse()
  }, [])

  console.log(userMessage)

  return (
    <div>
      {userMessage.map(message => (
        <p>{message.message}</p>
      ))}
    </div>
  )
  }

Answer 1

Some of the response in the array is object which make React fail to render. The 3rd to 5th items.

[
    {
        "message": "hej test"
    },
    {
        "message": "hej test",
        "id": "1"
    },
    {
        "message": {
            "mess": "Hi",
            "status": true
        }
    },
    {
        "message": {
            "mess": "Hi",
            "status": true
        }
    },
    {
        "message": {
            "mess": "Hi",
            "status": true
        }
    }
]

Answer 2

It seems like you have message as an object within the array. You must check if its an object and then render the required field

import React, { useState, useEffect } from 'react'
import { BrowserRouter, Switch, Route } from 'react-router-dom'
import axios from 'axios'


export const GetMessages = () => {
  const [userName, setUserName] = useState([]);
  const [userMessage, setUserMessage] = useState([]);

  const fetchResponse = async () => {
    try {
      const getResponse = await axios.get(
      'http://167.172.108.61/?storage=camilla_lofroth'
    )
    console.log(getResponse)
    setUserMessage(getResponse)
    } catch (error) {
      alert('Error')
    }
    return[]
  }  

  useEffect(() => {
    fetchResponse()
  }, [])

  console.log(userMessage)

  return (
    <div>
      {userMessage.map(message => (
        <p>{message.message !== null && typeof message.message === 'object'? message.message.mess: message.message }</p>
      ))}
    </div>
  )
}

Answer 3

Actually when you use axios, the data returned is inside of an object called data. Just like like with the fetch API where you have to add .json() to the response, you also have to destructure the data out of axios response.

In your case, it should be something like this

const fetchResponse = async () => {
    try {
      const getResponse = await axios.get(
      'http://167.172.108.61/?storage=camilla_lofroth'
    )
    Const data = await getResponse.data
    Console.log(data)
    setUserMessage(data)
    } catch (error) {
      alert('Error')
    }
    return[]
  }