reactjs - 类型“只读<{}>”上不存在属性“历史”

Question

我认为设置状态属性类型有问题，但不确定设置历史记录的正确方法是什么：

class Game extends React.Component<{}, {stepNumber : number, history : Array<any>, xIsNext : boolean } > {
      constructor(props) {
        super(props);
        this.state = {
          history: [
            {
              squares: Array(9).fill(null)
            }
          ],
          stepNumber: 0,
          xIsNext: true
        };
      }

此行失败：

const history = this.state.history.slice(0, this.state.stepNumber + 1);

有错误：

Property 'history' does not exist on type 'Readonly<{}>'

完整代码：

class Game extends React.Component<{}, {stepNumber : number, history : Array<any>, xIsNext : boolean } > {
  constructor(props) {
    super(props);
    this.state = {
      history: [
        {
          squares: Array(9).fill(null)
        }
      ],
      stepNumber: 0,
      xIsNext: true
    };
  }

  handleClick(i) {
    const history = this.state.history.slice(0, this.state.stepNumber + 1);
    const current = history[history.length - 1];
    const squares = current.squares.slice();
    if (calculateWinner(squares) || squares[i]) {
      return;
    }
    squares[i] = this.state.xIsNext ? "X" : "O";
    this.setState({
      history: history.concat([
        {
          squares: squares
        }
      ]),
      stepNumber: history.length,
      xIsNext: !this.state.xIsNext
    });
  }

  jumpTo(step) {
    this.setState({
      stepNumber: step,
      xIsNext: (step % 2) === 0
    });
  }

  render() {
    const history = this.state.history;
    const current = history[this.state.stepNumber];
    const winner = calculateWinner(current.squares);

    const moves = history.map((step, move) => {
      const desc = move ?
        'Go to move #' + move :
        'Go to game start';
      return (
        <li key={move}>
          <button onClick={() => this.jumpTo(move)}>{desc}</button>
        </li>
      );
    });

    let status;
    if (winner) {
      status = "Winner: " + winner;
    } else {
      status = "Next player: " + (this.state.xIsNext ? "X" : "O");
    }

    return (
      <div className="game">
        <div className="game-board">
          <Board
            squares={current.squares}
            onClick={i => this.handleClick(i)}
          />
        </div>
        <div className="game-info">
          <div>{status}</div>
          <ol>{moves}</ol>
        </div>
      </div>
    );
  }
}


export default Game;

标签： reactjstypescript