用React写井字棋游戏

目录

• 1.确定本地Node.js和npm版本
• 2.搭建React环境
• 3.项目css代码
• 3.做下井字棋的功能
• 配置游戏的历史记录功能

1.确定本地Node.js和npm版本

确定Node.js版本node -v，确定npm版本npm -v，满足生产要求

2.搭建React环境

在命令行上执行npx create-react-app my-app安装React运行的必要依赖以及工程目录结构，转至src目录中写源码，命令行中npm start可以在本地3000端口处查看代码运行的情况。

3.项目css代码

ody {
  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;
}

游戏的操作和逻辑用js实现，以下讨论cs文件的

3.做下井字棋的功能

js代码：

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

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

class Board extends React.Component {
  constructor(props){
  super(props);
  this.state={squares:Array(9).fill(null),xIsNext:true,};
}
  renderSquare(i) {
    return <Square value={this.state.squares[i]} onClick={()=>this.handleClick(i)}/>;
  }
  handleClick(i){
  const squares=this.state.squares.slice();
  if(calculateWinner(squares) || squares[i]){
    return;
  }
  squares[i]=this.state.xIsNext?'X':'O';
  this.setState({squares:squares,xIsNext:!this.state.xIsNext});
}

  render() {
  const winner=calculateWinner(this.state.squares);
  let status;
  if(winner){
    status='Winner: '+winner;
  }else{
    status='Next player: '+(this.state.xIsNext?'X':'O');
  }
    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>
    );
  }
}

class Game extends React.Component {
  render() {
    return (
      <div className="game">
        <div className="game-board">
          <Board />
        </div>
        <div className="game-info">
          <div>{/* status */}</div>
          <ol>{/* TODO */}</ol>
        </div>
      </div>
    );
  }
}

// ========================================

ReactDOM.render(
  <Game />,
  document.getElementById('root')
);

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 squares[a];
    }
  }
  return null;
}

配置游戏的历史记录功能

完善以上js文件

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

function Square(props) {
    return (
      <button className="square" onClick={props.onClick}>
        {props.value}
      </button>
      );
}

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

  render() {
    return (
      <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>
    );
  }
}

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

  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,}]), xIsNext:!this.state.xIsNext, stepNumber: history.length, });
  }

  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>
    );
  }
}

// ========================================

ReactDOM.render(
  <Game />,
  document.getElementById('root')
);

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 squares[a];
    }
  }
  return null;
}