这个来源于网上，不过代码改了不少，减少了些代码便于学习。
<!DOCTYPE html>
<html>
<body>
<h3>AI五子棋游戏</h3>
<canvas id="chess" width="450px" height="450px"></canvas>
<script>
var chressBord = []; //棋盘
var wins = []; //存放所有5个棋子在一条线上所有可能性，第一维存放y, 第二维存放x，第三维存放当前的可能性编号
var count = 0; //赢法总数量
var myWin = []; //我们赢法的统计数组
var computerWin = []; //计算机赢法的统计数组
var chess = document.getElementById("chess");
var context = chess.getContext('2d');
for(var i = 0; i < 15; i++)
{
chressBord[i] = [];
wins[i] = [];
for(var j = 0; j < 15; j++)
{
chressBord[i][j] = 0;
wins[i][j] = [];
}
}
//横线赢法
for(var i = 0; i < 15; i++)
for(var j = 0; j < 11; j++,count++)
for(var k = 0; k < 5; k++)
wins[i][j+k][count] = true;
//竖线赢法
for(var i = 0; i < 15; i++)
for(var j = 0; j < 11; j++,count++)
for(var k = 0; k < 5; k++)
wins[j+k][i][count] = true;
//正斜线赢法
for(var i = 0; i < 11; i++)
for(var j = 0; j < 11; j++,count++)
for(var k = 0; k < 5; k++)
wins[i+k][j+k][count] = true;
//反斜线赢法
for(var i = 0; i < 11; i++)
for(var j = 14; j > 3; j--,count++)
for(var k = 0; k < 5; k++)
wins[i+k][j-k][count] = true;
for(var i = 0; i < count; i++)
{
myWin[i] = 0; //这个数组很精髓，记录下棋后我方每一个位置在每种赢法的得分
computerWin[i] = 0;
}
chess.onclick = function(e) // 我，下棋
{
var i = Math.floor(e.offsetX / 30);
var j = Math.floor(e.offsetY / 30);
if(chressBord[i][j] == 0)
{
MoveStep(i,j,"red", 1, myWin);
computerAI();
}
}
// 计算机下棋，找玩家最容易赢的位置或者电脑最容易赢的位置
var computerAI = function ()
{
var myScore = [];
var computerScore = [];
var max = 0;
var u = 0, v = 0;
for(var i = 0; i < 15; i++)
{
myScore[i] = [];
computerScore[i] = [];
for(var j = 0; j < 15; j++)
{
myScore[i][j] = 0;
computerScore[i][j] = 0;
}
}
//找落子赢的概率最大坐标
for(var i = 0; i < 15; i++)
{
for(var j = 0; j < 15; j++)
{
for(var k = 0; k < count; k++) //遍历到i,j这个坐标时，计算谁的得分更高
{
if(chressBord[i][j] != 0 || !wins[i][j][k]) //当前i,j坐标还没落子
continue;
switch(myWin[k])
{
case 1: myScore[i][j] += 200; break;
case 2: myScore[i][j] += 400; break;
case 3: myScore[i][j] += 2000; break;
case 4: myScore[i][j] += 10000; break;
}
switch(computerWin[k])
{
case 1: computerScore[i][j] += 220; break;
case 2: computerScore[i][j] += 420; break;
case 3: computerScore[i][j] += 2100; break;
case 4: computerScore[i][j] += 20000; break;
}
}
if(myScore[i][j] > max) //如果玩家落子的分数多，就替换
{
max = myScore[i][j];
u = i;
v = j;
}
else if(myScore[i][j] == max) //如果玩家落子的分数跟原来最多分数一样多
{
if(computerScore[i][j] > computerScore[u][v]) //如果电脑在i,j落子的分数比u,v的分数多，就替换
{
u = i;
v = j;
}
}
if(computerScore[i][j] > max) //如果电脑下棋新位置分数比原来的多，就替换
{
max = computerScore[i][j];
u = i;
v = j;
}
else if(computerScore[i][j] == max) //如果电脑下棋新位置分数跟原来的一样多
{
if(myScore[i][j] > myScore[u][v]) //如果玩家落子的分数多，就准备把玩家最好的位置占掉
{
u = i;
v = j;
}
}
}
}
MoveStep(u,v,"blue", 2, computerWin);
}
var CheckWin = function(i, j, Role, WinArray)
{
for(var k = 0; k < count; k++)
if(wins[i][j][k]) // 将可能赢的情况都加1
{
WinArray[k]++;
if(WinArray[k] >= 5)
alert(Role + ': 恭喜，你赢了！')
}
}
//绘画棋盘
var drawChessBoard = function()
{
for(var i = 0; i < 15; i++)
{
context.moveTo(15 + i * 30 , 15);
context.lineTo(15 + i * 30 , 435);
context.moveTo(15 , 15 + i * 30);
context.lineTo(435 , 15 + i * 30);
context.stroke();
}
}
drawChessBoard(); // 画棋盘
var MoveStep = function(i,j,Role, ID, WinArray) //落子
{
context.beginPath();
context.arc(15 + i * 30, 15 + j * 30, 13, 0, 2 * Math.PI);// 画圆
context.closePath();
context.fillStyle = Role;
context.fill(); //填充颜色
chressBord[i][j] = ID; //玩家ID棋盘位置占位
CheckWin(i,j,Role, WinArray); //判断是否获胜，这里也很精髓，递归思想
}
</script>
</body>
</html>附原来的代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>AI五子棋游戏</title>
<style type='text/css'>
canvas {
display: block;
margin: 50px auto;
box-shadow: -2px -2px 2px #efefef, 5px 5px 5px #b9b9b9;
cursor: pointer;
}
.btn-wrap {
display: flex;
flex-direction: row;
justify-content:center;
}
.btn-wrap div {
margin: 0 10px;
}
div>span {
display: inline-block;
padding: 10px 20px;
color: #fff;
background-color: #EE82EE;
border-radius: 5px;
cursor: pointer;
}
div.unable span {
background: #D6D6D4;
color: #adacaa;
}
#result-wrap {text-align: center;}
</style>
</head>
<body>
<h3 id="result-wrap">AI五子棋</h3>
<canvas id="chess" width="450px" height="450px"></canvas>
<div class="btn-wrap">
<div id='restart' class="restart">
<span>重新开始</span>
</div>
<div id='goback' class="goback unable">
<span>悔棋</span>
</div>
<div id='return' class="return unable">
<span>撤销悔棋</span>
</div>
</div>
<script type="text/javascript" charset="utf-8">
var over = false;
var me = true; //我
var _nowi = 0, _nowj = 0; //记录自己下棋的坐标
var _compi = 0, _compj = 0; //记录计算机当前下棋的坐标
var _myWin = [], _compWin = []; //记录我，计算机赢的情况
var backAble = false, returnAble = false;
var resultTxt = document.getElementById('result-wrap');
var chressBord = [];//棋盘
for(var i = 0; i < 15; i++){
chressBord[i] = [];
for(var j = 0; j < 15; j++){
chressBord[i][j] = 0;
}
}
//赢法的统计数组
var myWin = [];
var computerWin = [];
//赢法数组
var wins = [];
for(var i = 0; i < 15; i++){
wins[i] = [];
for(var j = 0; j < 15; j++){
wins[i][j] = [];
}
}
var count = 0; //赢法总数
//横线赢法
for(var i = 0; i < 15; i++){
for(var j = 0; j < 11; j++){
for(var k = 0; k < 5; k++){
wins[i][j+k][count] = true;
}
count++;
}
}
//竖线赢法
for(var i = 0; i < 15; i++){
for(var j = 0; j < 11; j++){
for(var k = 0; k < 5; k++){
wins[j+k][i][count] = true;
}
count++;
}
}
//正斜线赢法
for(var i = 0; i < 11; i++){
for(var j = 0; j < 11; j++){
for(var k = 0; k < 5; k++){
wins[i+k][j+k][count] = true;
}
count++;
}
}
//反斜线赢法
for(var i = 0; i < 11; i++){
for(var j = 14; j > 3; j--){
for(var k = 0; k < 5; k++){
wins[i+k][j-k][count] = true;
}
count++;
}
}
// debugger;
for(var i = 0; i < count; i++){
myWin[i] = 0;
_myWin[i] = 0;
computerWin[i] = 0;
_compWin[i] = 0;
}
var chess = document.getElementById("chess");
var context = chess.getContext('2d');
context.strokeStyle = '#bfbfbf'; //边框颜色
var backbtn = document.getElementById("goback");
var returnbtn = document.getElementById("return");
window.onload = function(){
drawChessBoard(); // 画棋盘
}
document.getElementById("restart").onclick = function(){
window.location.reload();
}
// 我，下棋
chess.onclick = function(e){
if(over){
return;
}
if(!me){
return;
}
// 悔棋功能可用
backbtn.className = backbtn.className.replace( new RegExp( "(\\s|^)unable(\\s|$)" )," " );
var x = e.offsetX;
var y = e.offsetY;
var i = Math.floor(x / 30);
var j = Math.floor(y / 30);
_nowi = i;
_nowj = j;
if(chressBord[i][j] == 0){
oneStep(i,j,me);
chressBord[i][j] = 1; //我，已占位置
for(var k = 0; k < count; k++){ // 将可能赢的情况都加1
if(wins[i][j][k]){
// debugger;
myWin[k]++;
_compWin[k] = computerWin[k];
computerWin[k] = 6;//这个位置对方不可能赢了
if(myWin[k] == 5){
// window.alert('你赢了');
resultTxt.innerHTML = '恭喜，你赢了！';
over = true;
}
}
}
if(!over){
me = !me;
computerAI();
}
}
}
// 悔棋
backbtn.onclick = function(e){
if(!backAble) { return;}
over = false;
me = true;
// resultTxt.innerHTML = 'o(╯□╰)o，悔棋中';
// 撤销悔棋功能可用
returnbtn.className = returnbtn.className.replace( new RegExp( "(\\s|^)unable(\\s|$)" )," " );
// 我，悔棋
chressBord[_nowi][_nowj] = 0; //我，已占位置 还原
minusStep(_nowi, _nowj); //销毁棋子
for(var k = 0; k < count; k++){ // 将可能赢的情况都减1
if(wins[_nowi][_nowj][k]){
myWin[k]--;
computerWin[k] = _compWin[k];//这个位置对方可能赢
}
}
// 计算机相应的悔棋
chressBord[_compi][_compj] = 0; //计算机，已占位置 还原
minusStep(_compi, _compj); //销毁棋子
for(var k = 0; k < count; k++){ // 将可能赢的情况都减1
if(wins[_compi][_compj][k]){
computerWin[k]--;
myWin[k] = _myWin[i];//这个位置对方可能赢
}
}
resultTxt.innerHTML = '--益智五子棋--';
returnAble = true;
backAble = false;
}
// 撤销悔棋
returnbtn.onclick = function(e){
if(!returnAble) { return; }
// 我，撤销悔棋
chressBord[_nowi][_nowj] = 1; //我，已占位置
oneStep(_nowi,_nowj,me);
for(var k = 0; k < count; k++){
if(wins[_nowi][_nowj][k]){
myWin[k]++;
_compWin[k] = computerWin[k];
computerWin[k] = 6;//这个位置对方不可能赢
}
if(myWin[k] == 5){
resultTxt.innerHTML = '恭喜，你赢了！';
over = true;
}
}
// 计算机撤销相应的悔棋
chressBord[_compi][_compj] = 2; //计算机，已占位置
oneStep(_compi,_compj,false);
for(var k = 0; k < count; k++){ // 将可能赢的情况都减1
if(wins[_compi][_compj][k]){
computerWin[k]++;
_myWin[k] = myWin[k];
myWin[k] = 6;//这个位置对方不可能赢
}
if(computerWin[k] == 5){
resultTxt.innerHTML = 'o(╯□╰)o，计算机赢了，继续加油哦！';
over = true;
}
}
returnbtn.className += ' '+ 'unable';
returnAble = false;
backAble = true;
}
// 计算机下棋
var computerAI = function (){
var myScore = [];
var computerScore = [];
var max = 0;
var u = 0, v = 0;
for(var i = 0; i < 15; i++){
myScore[i] = [];
computerScore[i] = [];
for(var j = 0; j < 15; j++){
myScore[i][j] = 0;
computerScore[i][j] = 0;
}
}
for(var i = 0; i < 15; i++){
for(var j = 0; j < 15; j++){
if(chressBord[i][j] == 0){
for(var k = 0; k < count; k++){
if(wins[i][j][k]){
if(myWin[k] == 1){
myScore[i][j] += 200;
}else if(myWin[k] == 2){
myScore[i][j] += 400;
}else if(myWin[k] == 3){
myScore[i][j] += 2000;
}else if(myWin[k] == 4){
myScore[i][j] += 10000;
}
if(computerWin[k] == 1){
computerScore[i][j] += 220;
}else if(computerWin[k] == 2){
computerScore[i][j] += 420;
}else if(computerWin[k] == 3){
computerScore[i][j] += 2100;
}else if(computerWin[k] == 4){
computerScore[i][j] += 20000;
}
}
}
if(myScore[i][j] > max){
max = myScore[i][j];
u = i;
v = j;
}else if(myScore[i][j] == max){
if(computerScore[i][j] > computerScore[u][v]){
u = i;
v = j;
}
}
if(computerScore[i][j] > max){
max = computerScore[i][j];
u = i;
v = j;
}else if(computerScore[i][j] == max){
if(myScore[i][j] > myScore[u][v]){
u = i;
v = j;
}
}
}
}
}
_compi = u;
_compj = v;
oneStep(u,v,false);
chressBord[u][v] = 2; //计算机占据位置
for(var k = 0; k < count; k++){
if(wins[u][v][k]){
computerWin[k]++;
_myWin[k] = myWin[k];
myWin[k] = 6;//这个位置对方不可能赢了
if(computerWin[k] == 5){
resultTxt.innerHTML = 'o(╯□╰)o，计算机赢了，继续加油哦！';
over = true;
}
}
}
if(!over){
me = !me;
}
backAble = true;
returnAble = false;
var hasClass = new RegExp('unable').test(' ' + returnbtn.className + ' ');
if(!hasClass) {
returnbtn.className += ' ' + 'unable';
}
}
//绘画棋盘
var drawChessBoard = function() {
for(var i = 0; i < 15; i++){
context.moveTo(15 + i * 30 , 15);
context.lineTo(15 + i * 30 , 435);
context.stroke();
context.moveTo(15 , 15 + i * 30);
context.lineTo(435 , 15 + i * 30);
context.stroke();
}
}
//画棋子
var oneStep = function(i,j,me) {
context.beginPath();
context.arc(15 + i * 30, 15 + j * 30, 13, 0, 2 * Math.PI);// 画圆
context.closePath();
//渐变
var gradient = context.createRadialGradient(15 + i * 30 + 2, 15 + j * 30 - 2, 13, 15 + i * 30 + 2, 15 + j * 30 - 2, 0);
if(me){
gradient.addColorStop(0,'#0a0a0a');
gradient.addColorStop(1,'#636766');
}else{
gradient.addColorStop(0,'#d1d1d1');
gradient.addColorStop(1,'#f9f9f9');
}
context.fillStyle = gradient;
context.fill();
}
//销毁棋子
var minusStep = function(i,j) {
//擦除该圆
context.clearRect((i) * 30, (j) * 30, 30, 30);
// 重画该圆周围的格子
context.beginPath();
context.moveTo(15+i*30 , j*30);
context.lineTo(15+i*30 , j*30 + 30);
context.moveTo(i*30, j*30+15);
context.lineTo((i+1)*30 , j*30+15);
context.stroke();
}
</script>
</body>
</html>