使用.map() 在 object React 中迭代數組

Question

我正在嘗試迭代對象數組中的 throw 元素，但由於返回的數據不是數組而是 Object，因此 .map() 不能以簡單的方式使用。

API 返回如下結構

/玩家（端點）

{
  "players": [
    {
      "player_id": "Uy2sZ5ef",
      "player_name": "Foo",
      "player_team": "5c50bae023213348c4453aaf"      
    },
    {      
      "player_id": "h15sqI4D",
      "player_name": "Foo 2",
      "player_team": "5c50bae023213348c4453aaf"
    }
  ]
}

反應組件

export class Players extends Component {
    state = {
        players: []
    }

    componentDidMount() {
    API.get(`players/`).then(res => {
            console.log(res)
            this.setState({ players: res.data })
        })
    }

    render() {
        return (
            <section className="contents">

                { this.state.players.map(player => <li>{player.player_name}</li>)}

            </section>
        );
    }
}

Answer 1

如果您的數據看起來像 object，並且您只需要播放器，您應該：

    componentDidMount() {
    API.get(`players/`).then(res => {
            console.log(res)
            this.setState({ players: res.data.players }) // <-- get only the players
        })
    }

Answer 2

您可能對功能組件感興趣：

const Players = () => {
  const [players, setPlayers] = useState([]);

  useEffect(() => {
    API.get(`players/`).then(res => {
      console.log(res);
      setPlayers(res.data.players); // <-- get only the players
    });
  }, []);

  return (
    <section className="contents">
      {players.map(player => (
        <li>{player.player_name}</li>
      ))}
    </section>
  );
};