React 组件传参

class Square extends React.Component {
  render() {
    return (
      <button className="square">
        {this.props.num}
      </button>
    );
  }
}

class Board extends React.Component {
  renderSquare(i) {
    return <Square num={i}/>;
  }

  render() {
    const status = 'Next player: X';

    return (
      <div>
        <div className="status">{status}</div>
        <div className="board-row">
          {this.renderSquare(0)}
          {this.renderSquare(1)}
          {this.renderSquare(2)}
        </div>
        <div className="board-row">
          {this.renderSquare(3)}
          {this.renderSquare(4)}
          {this.renderSquare(5)}
        </div>
        <div className="board-row">
          {this.renderSquare(6)}
          {this.renderSquare(7)}
          {this.renderSquare(8)}
        </div>
      </div>
    );
  }
}

renderSquare(i) {
  return <Square num={i}/>;
}

return (
     <button className="square">
       {this.props.num}
     </button>
   );