<!DOCTYPE HTML>
<html>
<body>
<canvas id="myCanvas" width="400" height="400" style="border:1px solid #c3c3c3;"></canvas>
<script type="text/javascript">
var c = document.getElementById("myCanvas");
var time = 160; //蛇的速度
var cxt = c.getContext("2d");
var x = y = 8;
var a = 0; //食物坐标
var t = 10; //舍身长
var map = []; //记录蛇运行路径
var size = 8; //蛇身单元大小
var direction = 2; // 1 向上 2 向右 0 左 3下
interval = window.setInterval(set_game_speed, time); // 移动蛇
function set_game_speed() { // 移动蛇
switch (direction) {
case 1:
y = y - size;
break;
case 2:
x = x + size;
break;
case 0:
x = x - size;
break;
case 3:
y = y + size;
break;
}
if (x > 400 || y > 400 || x < 0 || y < 0) {
alert("你挂了,失败原因:碰壁了.....");
window.location.reload();
}
for (var i = 0; i < map.length; i++) {
if (parseInt(map[i].x) == x && parseInt(map[i].y) == y) {
alert("你挂了,失败原因:撞到自己.....");
window.location.reload();
}
}
if (map.length > t) { //保持舍身长度
var cl = map.shift(); //删除数组第一项，并且返回原元素
cxt.clearRect(cl['x'], cl['y'], size, size);
};
map.push({
'x': x,
'y': y
}); //将数据添加到原数组尾部
cxt.fillStyle = "pink"; //内部填充颜色
cxt.strokeStyle = "pink"; //边框颜色
cxt.fillRect(x, y, size, size); //绘制矩形
if ((a * 8) == x && (a * 8) == y) { //吃食物
rand_frog();
t++;
}
}
document.onkeydown = function(e) { //改变蛇方向
var code = e.keyCode - 37;
switch (code) {
case 1:
direction = 1;
break; //上
case 2:
direction = 2;
break; //右
case 3:
direction = 3;
break; //下
case 0:
direction = 0;
break; //左
}
}
// 随机放置食物
function rand_frog() {
a = Math.ceil(Math.random() * 50);
cxt.fillStyle = "#000000"; //内部填充颜色
cxt.strokeStyle = "#000000"; //边框颜色
cxt.fillRect(a * 8, a * 8, 8, 8); //绘制矩形
}
// 随机放置食物
rand_frog();
</script>
</body>
</html>
