React井字棋后续功能完善

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';function Square(props) {return(<button className="square" onClick={props.onClick1}>{props.value}</button>);
}
class Board extends React.Component {renderSquare(i) {return (<Square value={this.props.squares[i]}onClick1={()=>this.props.onClick(i)}/>);}render() {return(<div>{//3.使用两个循环来渲染出棋盘的格子，而不是在代码里写死（hardcode）Array(3).fill(null).map((itemx, x) => (<div className="board-row" key={x}>{Array(3).fill(null).map((itemy, y) => (this.renderSquare(3 * x + y)))}</div>))}</div>);}
}class Game extends React.Component {constructor(props){super(props);this.state = {history:[{squares:Array(9).fill(null)}],position:[{row : null,column: null,}],stepNumber: 0,xIsNext:true,sort:true,}}handleClick(i){//position记录坐标const position =this.state.position.slice(0,this.state.stepNumber + 1);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';const row = parseInt(i%3+1);const column = parseInt(i/3+1);this.setState({history:history.concat([{squares:squares,}]),position:position.concat([{row : row,column: column,}]),stepNumber: history.length,xIsNext:!this.state.xIsNext,});}jumpTo(step) {this.setState({stepNumber: step,xIsNext: (step % 2) === 0,});}changeSquence(){this.setState({sort:!this.state.sort,});}render() {//计算winner，为了保持react的不可变性，需要复制对象const history=this.state.history;const position = this.state.position;const current=history[this.state.stepNumber];const winner=calculateWinner(current.squares);const moves = history.map((step,move)=>{//1.加入行列号const desc = move ?'go to move #' + move + '最后落棋点：('+position[move].row+ ','+position[move].column+ ')':'go to start';//2.在历史记录列表中加粗显示当前选择的项目。let font =  (move==this.state.stepNumber)?{fontWeight:'bold'}:{fontWeight:'normal'};return (<li key={move.id}><button style={font} onClick={()=>this.jumpTo(move)} >{desc}</button></li>);});let status;// 5.每当有人获胜时，高亮显示连成一线的 3 颗棋子。if(winner){status = "Winner：" + winner.winnerName;for (let i of winner.squares){document.getElementsByClassName('square')[i].style= "background: lightblue;";}// 6.当无人获胜时，显示一个平局的消息。}else if (this.state.stepNumber===9){status='No winner';}else {status = 'Next player: '+(this.state.xIsNext ? 'X':'O');}return (<div className="game"><div className="game-board"><Boardsquares={current.squares}onClick={(i)=>this.handleClick(i)}/></div><div className="game-info"><div>{ status }</div>{/*4.添加一个可以升序或降序显示历史记录的按钮。*/}<button onClick={()=>this.changeSquence()}>{this.state.sort ? "倒序":"正序"}</button><ol>{this.state.sort ? moves:moves.reverse()}</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, b, c],winnerName:squares[a],};}}return null;
}