docusaurus/website/pages/tictactoe.js
2018-08-23 21:46:14 +08:00

142 lines
3.2 KiB
JavaScript

import React from 'react';
import Helmet from 'react-helmet';
import style from './tictactoe.css';
function Square(props) {
return (
<button className={style.square} onClick={props.onClick}>
{props.value}
</button>
);
}
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;
}
class Board extends React.Component {
renderSquare(i) {
return (
<Square
value={this.props.squares[i]}
onClick={() => this.props.onClick(i)}
/>
);
}
render() {
return (
<div>
<div className={style.boardRow}>
{this.renderSquare(0)}
{this.renderSquare(1)}
{this.renderSquare(2)}
</div>
<div className={style.boardRow}>
{this.renderSquare(3)}
{this.renderSquare(4)}
{this.renderSquare(5)}
</div>
<div className={style.boardRow}>
{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)
}
],
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
}
]),
stepNumber: history.length,
xIsNext: !this.state.xIsNext
});
}
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={style.game}>
<Helmet title="Tic Tac Toe" />
<div className={style.gameBoard}>
<Board squares={current.squares} onClick={i => this.handleClick(i)} />
</div>
<div className={style.gameInfo}>
<div>{status}</div>
<ol>{moves}</ol>
</div>
</div>
);
}
}
export default Game;