React官网 - 井字棋 - 游戏改进参考答案（含汉化和完整范例代码）

import React from "react";
import ReactDOM from "react-dom";
import "./index.css";

function Square(props) {
  return (
    <button
      className={
        (props.winList || []).includes(props.num) ? "square win" : "square"
      }
      onClick={props.onClick}
    >
      {props.value}
    </button>
  );
}

class Board extends React.Component {
  renderSquare(i) {
    return (
      <Square
        winList={this.props.winList}
        num={i}
        key={i.toString()}
        value={this.props.squares[i]}
        onClick={() => this.props.onClick(i)}
      />
    );
  }

  render() {
    let arr = Array(3).fill(null);
    let num = 0;

    return (
      <div>
        {arr.map(() => (
          <div className="board-row" key={num.toString()}>
            {arr.map(() => {
              let cloumn = this.renderSquare(num);
              num = num + 1;
              return cloumn;
            })}
          </div>
        ))}
      </div>
    );
  }
}

class Game extends React.Component {
  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,
          position: {
            row: Math.floor(i / 3) + 1,
            cloumn: (i % 3) + 1,
          },
          player: this.state.xIsNext ? "X" : "O",
          stepNumber: this.state.stepNumber + 1,
        },
      ]),
      stepNumber: history.length,
      xIsNext: !this.state.xIsNext,
    });
  }
  jumpTo(step) {
    this.setState({
      stepNumber: step,
      xIsNext: step % 2 === 0,
    });
  }
  asc() {
    this.setState({
      history: this.state.history.sort((a, b) => a.stepNumber - b.stepNumber),
    });
  }
  des() {
    this.setState({
      history: this.state.history.sort((a, b) => b.stepNumber - a.stepNumber),
    });
  }
  render() {
    const history = this.state.history;
    let current = {};
    if (history.length > 1) {
      history.forEach((item) => {
        if (item.stepNumber === this.state.stepNumber) {
          current = item;
        }
      });
    } else {
      current = history[this.state.stepNumber];
    }

    const result = calculateWinner(current.squares);
    let winner = "";

    if (result) {
      winner = result.winner;
    }

    const moves = history.map((item, move) => {
      const desc = move
        ? `返回到第 ${item.stepNumber} 步 - 第 ${item.position.row} 行，第 ${item.position.cloumn} 列 - 玩家 ${item.player} `
        : "重新开始游戏";
      return (
        <li key={move}>
          <button
            className={this.state.stepNumber === item.stepNumber ? "bold" : ""}
            onClick={() => this.jumpTo(move)}
          >
            {desc}
          </button>
        </li>
      );
    });
    let status;
    if (winner) {
      status = "最终胜利者的玩家: " + winner;
    } else {
      if (this.state.stepNumber >= 9) {
        status = "最终结果：平局";
      } else {
        status = "请玩家  " + (this.state.xIsNext ? "X" : "O") + " 落子";
      }
    }
    return (
      <div className="game">
        <div className="game-board">
          <Board
            winList={result && result.winList}
            squares={current.squares}
            onClick={(i) => this.handleClick(i)}
          />
        </div>
        <div className="game-info">
          <div>{status}</div>
          <button onClick={() => this.asc()}>升序</button>
          <button onClick={() => this.des()}>降序</button>
          <ul>{moves}</ul>
        </div>
      </div>
    );
  }
}

function calculateWinner(squares) {
  const lines = [
    [0, 1, 2],
    [3, 4, 5],
    [6, 7, 8],
    [0, 3, 6],
    [1, 4, 7],
    [2, 5, 8],
    [0, 4, 8],
    [2, 4, 6],
  ];
  for (let i = 0; i < lines.length; i++) {
    const [a, b, c] = lines[i];
    if (squares[a] && squares[a] === squares[b] && squares[a] === squares[c]) {
      return {
        winner: squares[a],
        winList: [a, b, c],
      };
    }
  }
  return null;
}

const root = ReactDOM.createRoot(document.getElementById("root"));
root.render(<Game />);

body {
  font: 14px "Century Gothic", Futura, sans-serif;
  margin: 20px;
}

ol,
ul {
  padding-left: 30px;
}

.board-row:after {
  clear: both;
  content: "";
  display: table;
}

.status {
  margin-bottom: 10px;
}

.square {
  background: #fff;
  border: 1px solid #999;
  float: left;
  font-size: 24px;
  font-weight: bold;
  line-height: 34px;
  height: 34px;
  margin-right: -1px;
  margin-top: -1px;
  padding: 0;
  text-align: center;
  width: 34px;
}

.square:focus {
  outline: none;
}

.kbd-navigation .square:focus {
  background: #ddd;
}

.game {
  display: flex;
  flex-direction: row;
}

.game-info {
  margin-left: 20px;
}

.bold{
  font-weight: bold;
}

.win{
  color: red;
}