<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>贪吃蛇 作者:记忆中的马肠河</title> <script type="text/javascript"> window.onload = function () { var snake = { //移动方向 fangxiang: "left", //蛇身 snakeBody: [], box: document.getElementById("snakeBox"), //移动 move: function () { var timer = ""; //判断是否GameOver var isFailed = function () { //判断蛇头是否碰到蛇身 var isHeadRunIntoBody=function(){ var t=false; for(var i=0;i<snake.snakeBody.length-1;i++){ if(snake.snakeBody[snake.snakeBody.length-1].x==snake.snakeBody[i].x&& snake.snakeBody[snake.snakeBody.length-1].y==snake.snakeBody[i].y ){ t=true; break; } } return t; } //判断条件：是否蛇身碰到蛇头、是否蛇头碰到墙壁 if ( isHeadRunIntoBody()|| snake.snakeBody[snake.snakeBody.length - 1].x > snake.box.offsetLeft + parseInt(snake.box.style.borderWidth) + snake.box.clientWidth - 10 || snake.snakeBody[snake.snakeBody.length - 1].x < snake.box.offsetLeft + parseInt(snake.box.style.borderWidth) || snake.snakeBody[snake.snakeBody.length - 1].y < snake.box.offsetTop + parseInt(snake.box.style.borderWidth) || snake.snakeBody[snake.snakeBody.length - 1].y > snake.box.offsetTop + parseInt(snake.box.style.borderWidth) + snake.box.clientWidth - 10 ) { //清除定时器 clearTimeout(timer); alert("Game over!"); return false; } } //存放蛇头 var snakeHead = snake.snakeBody[snake.snakeBody.length - 1]; //去除蛇尾 var sheWei = snake.snakeBody.shift(); switch (snake.fangxiang) { case "up": sheWei.x = snakeHead.x; sheWei.y = snakeHead.y - 10; break; case "down": sheWei.x = snakeHead.x; sheWei.y = snakeHead.y + 10; break; case "left": sheWei.x = snakeHead.x - 10; sheWei.y = snakeHead.y; break; case "right": sheWei.x = snakeHead.x + 10; sheWei.y = snakeHead.y; break; default: break; } //把蛇尾放到蛇头 snake.snakeBody.push(sheWei); //每次移动蛇身，都去吃食物. snake.eatFood(); //是否失败 var ISF = isFailed(); //如果失败，不再绘制； if (!ISF && ISF != undefined) { return; } else { snake.drawSnake(); } //蛇身移动的定时器 timer = setTimeout(snake.move, 500); }, drawSnake: function () { //清空已绘制的蛇身 var bc = snake.box.childNodes; for (var i = 0, len = bc.length; i < len; i++) { var tn = bc[i]; if (tn) { var tng = tn.tagName; if (tng) { var id = bc[i].getAttribute("id") if (tng.toLowerCase() == "div" && id != "foodDiv") { snake.box.removeChild(bc[i]); //没删除一个节点索引退一步 i-=1; } } } } //判断是否是第一次加载蛇身，如果是，则添加蛇头 if (snake.snakeBody.length == 0) { var a = {}; do{ a.x = Math.floor(19 * Math.random()) * 10 + snake.box.offsetLeft + parseInt(snake.box.style.borderWidth); a.y = Math.floor(19 * Math.random()) * 10 + snake.box.offsetTop + parseInt(snake.box.style.borderWidth); }while((function(){ //第一次添加蛇头的时候不能让蛇头挨着边框 if(a.x==snake.box.offsetLeft + parseInt(snake.box.style.borderWidth) ||a.x+10==snake.box.offsetLeft + parseInt(snake.box.style.borderWidth)+snake.box.clientWidth ||a.y==snake.box.offsetTop+parseInt(snake.box.style.borderWidth) ||a.y+10==snake.box.offsetTop+parseInt(snake.box.style.borderWidth)+snake.box.clientHeight ){ return true; }else{ return false; } })()); snake.snakeBody.push(a); } //遍历存放蛇的数组并绘制在页面上 for (var b in snake.snakeBody) { var d = document.createElement("div"); d.style.backgroundColor = 'red'; d.style.border = "0px solid green"; d.style.position = 'absolute'; d.style.zIndex = '1'; d.style.width = '10px'; d.style.height = '10px'; d.style.left = snake.snakeBody[b].x + "px"; d.style.top = snake.snakeBody[b].y + "px"; snake.box.appendChild(d); } return snake; }, eatFood: function () { var foodObj = food.getFood(); //判断蛇头是否与食物重合，如果是，则把食物作为蛇头 if ( snake.snakeBody[snake.snakeBody.length - 1].x == foodObj.offsetLeft && snake.snakeBody[snake.snakeBody.length - 1].y == foodObj.offsetTop ) { var o = {}; switch (snake.fangxiang) { case "left": o.x = snake.snakeBody[snake.snakeBody.length - 1].x - 10; o.y = snake.snakeBody[snake.snakeBody.length - 1].y; break; case "right": o.x = snake.snakeBody[snake.snakeBody.length - 1].x + 10; o.y = snake.snakeBody[snake.snakeBody.length - 1].y; break; case "up": o.x = snake.snakeBody[snake.snakeBody.length - 1].x; o.y = snake.snakeBody[snake.snakeBody.length - 1].y - 10; break; case "down": o.x = snake.snakeBody[snake.snakeBody.length - 1].x; o.y = snake.snakeBody[snake.snakeBody.length - 1].y + 10; break; default: break; } //把原来的食物删除 snake.box.removeChild(foodObj); //把吃到的食物加到蛇头 snake.snakeBody.push(o); //重新绘制食物 food.foodMake(); } } } var food = { //生成食物 foodMake: function () { //定义食物出现的位置 var x, y; do { x = Math.floor(19 * Math.random()) * 10 + snake.box.offsetLeft + parseInt(snake.box.style.borderWidth); y = Math.floor(19 * Math.random()) * 10 + snake.box.offsetTop + parseInt(snake.box.style.borderWidth); } while ((function () { //蛇身是否在该位置，如果蛇身和食物重合则重新生成食物 var t = false; for (var o in snake.snakeBody) { t = snake.snakeBody[o].x == x && snake.snakeBody[o].y == y if (t) { break; } } return t; })()); var d = document.createElement("div"); d.style.backgroundColor = 'red'; d.style.border = "0px solid green"; d.style.position = 'absolute'; d.style.zIndex = '1'; d.style.width = '10px'; d.style.height = '10px'; d.setAttribute("id", "foodDiv"); //设置食物的ID用于区别蛇身 d.style.top = x + "px"; d.style.left = y + "px"; return snake.box.appendChild(d); //返回新生成的食物 }, //得到食物 getFood: function () { return document.getElementById("foodDiv"); } } //先绘制食物 food.foodMake(); //绘制并移动蛇身 snake.drawSnake().move(); //控制方向键 document.onkeydown = function (event) { var e = event || window.event; switch (e.keyCode) { case 37: if (snake.fangxiang != "right") { snake.fangxiang = "left"; } break; case 38: if (snake.fangxiang != "down") { snake.fangxiang = "up"; } break; case 39: if (snake.fangxiang != "left") { snake.fangxiang = "right"; } break; case 40: if (snake.fangxiang != "up") { snake.fangxiang = "down"; } default: break; } } } </script> </head> <body style='text-align: center'> <div id='snakeBox' style='border: 1px solid black; 200px; height: 200px'> </div> </body> </html>
原文地址：http://www.cnblogs.com/zhangwei412827/archive/2013/03/25/2980180.html