react井字棋小游戏实现及优化
react井字棋小游戏实现及优化
主要参考：官方文档
本文章主要是在官方示例的基础上，做了一些优化，并且完成了官方文档最后的
改进要求。
下面是我的代码。
index.js:
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
function Square(props) {
//想写的组件只包含一个 render 方法，并且不包含 state，那么使用函数组件就会更简单
return (
<button className="square" onClick={props.onClick} style={props.styles}>
{props.value}
</button>
)
}
function test() { }
class Board extends React.Component {
renderSquare(j) {
var boardRaw = [];
const column = 3;
const raw = 3;
for (let i = 0; i < column; i++) {
boardRaw.push(<Square key={i + j * raw}
value={this.props.squares[i + j * raw]}
onClick={() => this.props.onClick(i + j * raw)}
styles={this.props.styles(i + j * raw)}
/>)
}
return boardRaw;
}
render() {
const raw = 3;
var boardAll = [];
for (let j = 0; j < raw; j++) {
boardAll.push(
<div className="board-row" key={j}>
{this.renderSquare(j)}
</div>);
}
return (
<div>
{boardAll}
</div>
);
}
}
class Game extends React.Component {
constructor(props) {
super(props);
this.state = {
history: [{
squares: Array(9).fill(null),
nowCoordinate: null,
}],
xIsNext: true,
stepNumber: 0,
//历史记录排序方式
descendingOrder: false,
};
}
handleWinnerStyle(winnerLine, i) {
const styles = {
background: "yellow"
};
if (winnerLine && winnerLine.indexOf(i) > -1) {
return styles;
}
return null;
}
handleClick(i) {
//创建副本
const history = this.state.history.slice(0, this.state.stepNumber + 1);
const current = history[history.length - 1];
const squares = current.squares.slice();
const column = 3;
const raw = 3;
var nowColumn = (i + 1) % column === 0 ? raw : (i + 1) % column;
var nowRaw = parseInt(i / raw) + 1;
if (calculateWinner(squares) || squares[i]) {
return;
}
squares[i] = this.state.xIsNext ? 'X' : 'O';
this.setState({
history: history.concat([{
squares: squares,
//当前坐标
nowCoordinate: [nowColumn, nowRaw],
}]),
stepNumber: history.length,
xIsNext: !this.state.xIsNext,
//历史记录排序方式
descendingOrder: this.state.descendingOrder,
});
}
jumpTo(step) {
this.setState({
stepNumber: step,
xIsNext: (step % 2) === 0,
});
}
/**
* @function 修改用于判断历史记录正序/逆序显示的参数descendingOrder
* */
reverseHistory = () => {
const { descendingOrder } = this.state;
this.setState({
descendingOrder: !descendingOrder
})
}
render() {
// let { lines } = this.state;
const { history, stepNumber, descendingOrder, } = this.state;
// const history = this.state.history;
const current = history[stepNumber];
const winnerLine = calculateWinner(current.squares);
var localCounter = 1;
//map(value,index)
const moves = history.map((step, move) => {
const desc = move ?
'第 ' + move + ' 步,落点（' + step.nowCoordinate + ')' :
'游戏初始化';
//加粗显示当先记录
return (
<li key={localCounter++}>
<button class={move === stepNumber ? 'currentButton' : 'button'} onClick={() => this.jumpTo(move)}>{desc}</button>
</li>
);
});
//要在Game渲染的时候进行
if (descendingOrder) {
moves.reverse();
}
let status;
if (winnerLine) {
const winner = current.squares[winnerLine[0]];
status = '赢家:' + winner;
//每当有人获胜时，高亮显示连成一线的 3 颗棋子。
} else if (this.state.stepNumber === 9) {
status = '平局';
} else {
status = '轮到谁走了: ' + (this.state.xIsNext ? 'X' : 'O');
}
return (
<div className="game">
<div className="game-board">
<Board
squares={current.squares}
onClick={(i) => this.handleClick(i)}
styles={(i) => this.handleWinnerStyle(winnerLine, i)}
/>
</div>
<div className="game-info">
<div>{status}</div>
<button
className='button'
onClick={() => this.reverseHistory()}
>
{descendingOrder ? '降序排列' : '升序排列'}
</button>
{/* <button onClick={() => history.reverse()}>反转列表</button> */}
<ol>{moves}</ol>
</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 lines[i];
}
}
return null;
}
// ========================================
ReactDOM.render(
<Game />,
document.getElementById('root')
);
// 在游戏历史记录列表显示每一步棋的坐标，格式为 (列号, 行号)。-ok
// 在历史记录列表中加粗显示当前选择的项目。-ok
// 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）。-ok
// 添加一个可以升序或降序显示历史记录的按钮。-ok
// 每当有人获胜时，高亮显示连成一线的 3 颗棋子。-ok
// 当无人获胜时，显示一个平局的消息。-ok
Index.css
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;
}
.currentButton {
margin-top: 5px;
font-weight: 900;
}
.button {
margin-top: 5px;
}
最终效果：
我的git仓库地址：
