JavaScript 实例 可以看看

<head>
<meta content-type="text/html;charset=utf-8"/>
<style>
#table {
 position:absolute;
 left:0;
 top:0;
 z-index:6;
 width :100%;
 height:100%;
 border:"1px solid black";
}
#table td {
 width:18;
 height:18;
 background-color:yellow;
 padding:1;
}
#info {
 position:relative;
 top:-18;
 left:591;
 width :100;
 height:150;
 background-color:blue;
}
</style>
<script >
Game = {
 BlockWidth : 20,
 GameState :"pause",
 Level : 1,
 Scoure : 0,
 Option :{
  init:function(){
   this.speed = 200-(Game.Level-1)*50;
   //this.foodPositionLevel = 1;
   this.foodNumOfsucced = 10+((Game.Level-1)*5);
   this.eatDeficultLevel = 16-Game.Level;
  }
 },
 Map : {
  init : function(left,top,width,height,foodNum){
   this.food = [];
   this.foodNum = foodNum;
   this.left = left;
   this.top = top;
   this.width = width;
   this.height = height;
   this.instance = document.createElement("div");
   this.instance.setAttribute("id","map");
   this.instance.style.position = "absolute";
   this.instance.style.left = left;
   this.instance.style.top = top;
   //this.instance.style.offsetWidth = width;
   //this.instance.style.offsetHeight = height;
   this.instance.style.width = width;
   this.instance.style.height = height;
   this.instance.style.backgroundColor = "gray";
   document.getElementById("adiv").appendChild(this.instance);
   var table = document.createElement("table");
   table.setAttribute("id","table");
   var frag = document.createDocumentFragment();
   frag.appendChild(table);
   for(var i = 0;i<600;i+=Game.BlockWidth){
    var row = table.insertRow(-1);
    for(var j =0;j<600;j+=Game.BlockWidth){
     var cell = row.insertCell(-1);
     //cell.innerHTML = "";
    }
   }
   this.instance.appendChild(frag);
  },
  createOrRefreshFood: function(){
   var ran;
   var tempRan;
   var foodPosLeft,foodPosTop;
   for(var i=0;i<this.foodNum;i++){
    if(!this.food[i]){
     this.food[i] = Game.Food.create(Game.BlockWidth-2,Game.BlockWidth-2,"red");
     this.instance.appendChild(this.food[i]);
    }
    //写了个关数越高,食物越靠近边沿的算法
    ran = Math.random();
    if(parseInt(ran*100) % 2 == 0 ){
     tempRan = (1/(Game.Level*2))*ran;
    }else{
     tempRan = 1-(1/(Game.Level*2))*ran;
    }
    if(parseInt(ran*1000) % 3 == 0 ){
     foodPosLeft = tempRan*(this.width-20) + this.left;
     foodPosLeft = foodPosLeft - foodPosLeft%20
     foodPosTop = ran*(this.height-20) + this.top;
     foodPosTop = foodPosTop - foodPosTop%20;
    }else if(parseInt(ran*1000) % 3 == 1){
     foodPosLeft = ran*(this.width-20) + this.left;
     foodPosLeft = foodPosLeft - foodPosLeft%20;
     foodPosTop = tempRan*(this.height-20) + this.top;
     foodPosTop = foodPosTop - foodPosTop % 20;
    }else{
     foodPosLeft = tempRan*(this.width-20) + this.left;
     foodPosLeft = foodPosLeft - foodPosLeft%20;
     foodPosTop = tempRan*(this.height-20) + this.top;
     foodPosTop = foodPosTop - foodPosTop % 20;
    }
    this.food[i].style.left = foodPosLeft;
    this.food[i].style.top = foodPosTop;
   }
  }
 },
 Food : {
  create : function(width,height,color){
     this.width = width;
     this.height = height;
     this.color = color;
     this.instance = document.createElement("div");
     this.instance.style.position = "absolute";
     this.instance.style.zIndex = "9";
     this.instance.style.width = width;
     this.instance.style.height = height;
     this.instance.style.backgroundColor = color;
     return this.instance;
    }
 },
 Snack : {
  init: function(defaultFoodNum){
   this.foodNum = defaultFoodNum;
   this.foodNumOfEat = 0;
   this.instance = [];
   this.derect = -1; // -1 = left,1=right,-2=up,2=down
   this.instance[0] = document.createElement("div");
   this.instance[0].style.position = "absolute";
   this.instance[0].style.backgroundColor = "black";
   this.instance[0].style.zIndex = "9";
   this.instance[0].style.width = Game.BlockWidth;
   this.instance[0].style.height = Game.BlockWidth;
   this.instance[0].style.left = 200;
   this.instance[0].style.top = 200;
   this.tail = null;
   this.instance[0].style.border = "2px  solid   white";
   Game.Map.instance.appendChild(this.instance[0]);
   for(var i=1;i<this.foodNum;i++){
    this.instance[i] = this.instance[0].cloneNode(true);
    this.instance[i].style.width = Game.BlockWidth;
    this.instance[i].style.height = Game.BlockWidth;
    this.instance[i].style.left = (parseInt(this.instance[i-1].style.left)+ Game.BlockWidth);
    this.instance[i].style.top = 200;
    this.instance[i].style.backgroundColor = "black";
    this.instance[i].style.border = "2px  solid   white";
    //this.instance[i].style.borderColor = "red";
    Game.Map.instance.appendChild(this.instance[i]);
   }
  },
  move:function(derect){
   if(derect + this.derect!=0){
    this.derect = derect;
   }
   var head = {};
   head.left = parseInt(this.instance[0].style.left);
   head.top = parseInt(this.instance[0].style.top);
   switch (this.derect){
     case -1:{
      this.instance[0].style.left = parseInt(this.instance[0].style.left)-Game.BlockWidth;
      break;
      }
     case 1:{
      this.instance[0].style.left = parseInt(this.instance[0].style.left)+Game.BlockWidth;
      break;
     }
     case -2:{
      this.instance[0].style.top = parseInt(this.instance[0].style.top)-Game.BlockWidth;
      break;
     }
     case 2:{
      this.instance[0].style.top = parseInt(this.instance[0].style.top)+Game.BlockWidth;
      break;
     }
    }
   if(this.tail!=null){
     this.foodNum++;
   }
   if(this.foodNum>1){
    for(var i=this.foodNum-1;i>1;i--){
     this.instance[i].style.left = this.instance[i-1].style.left;
     this.instance[i].style.top = this.instance[i-1].style.top;
    }
    if(this.tail!=null){
     Game.Map.instance.appendChild(this.tail);
     this.tail = null;
    }
    this.instance[1].style.left = head.left;
    this.instance[1].style.top = head.top;
   }
   if(this.isFull()){
    alert("恭喜您,顺利闯过第"+Game.Level+"关");
    clearInterval(Game.timing);
    if(Game.Level>5){
     alert("you win!");
    }else{
     Game.Level++;
     $("act").innerHTML = Game.Level;
     Game.Option.init();
    }
   }else if(this.isDead()){
    clearInterval(Game.timing);
    window.onkeydown = null;
    alert("you fail");
   }else{
    this.eat();
   }
  },
  eat : function(){
   var map = Game.Map;
   var head = this.instance[0];
   for(var i=0;i<map.food.length;i++){
    if(Math.abs(parseInt(this.instance[0].style.left)-parseInt(map.food[i].style.left))<=Game.Option.eatDeficultLevel
     && Math.abs(parseInt(this.instance[0].style.top)-parseInt(map.food[i].style.top))<=Game.Option.eatDeficultLevel) {
     //alert("eat!");
     this.tail = this.instance[this.instance.length] = this.instance[0].cloneNode(true); 
     var foodEated = map.food[i];
     for(var j=i+1;j<map.food.length;j++){
      map.food[j-1] = map.food[j];
     }
     map.food.length--;
     foodEated.parentNode.removeChild(foodEated);
     this.foodNumOfEat++;
     //alert(Game.Scoure);
     Game.Scoure = Game.Scoure + (100*Game.Level);
     //alert($("scoure"));
     $("scoure").innerHTML = ""+Game.Scoure;
     break;
    }
   }
   if(map.food.length<=0){
    map.createOrRefreshFood(map.foodNum);
   }
  },
  isFull : function(){
   //alert(this.foodNumOfEat);
   //alert(Game.foodNumOfsucced);
   return this.foodNumOfEat >= Game.Option.foodNumOfsucced;
  },
  isDead : function(){
   var map = Game.Map;
   if(
    parseInt(this.instance[0].style.left) < map.left
    || parseInt(this.instance[0].style.left) >= (map.left+map.width)
    || parseInt(this.instance[0].style.top) < map.top
    || parseInt(this.instance[0].style.top) >= (map.top + map.height) ) {
    return true;
    }
   for(var i=1;i<this.foodNum;i++){
    if(this.instance[0].style.left == this.instance[i].style.left
     && this.instance[0].style.top == this.instance[i].style.top){
      return true; 
     }
   }
  }
 },
 GameStart :function(level){
  this.Map.init(0,0,600,600,1);
  this.Map.createOrRefreshFood();
  this.Snack.init(6);
  this.Option.init(level);
  var gameItsSelf = this;
  //if(!window.onkeydown){
  // window.onkeydown = document.body.onkeydown;
  //}
  //alert(document.body.onkeydown);
  window.onkeydown = document.body.onkeydown = function(event){
   event = window.event||event;
   var keyCode = event.keyCode;
   //alert(keyCode);
   if(keyCode==32){
    //alert("暂停");
    if(Game.GameState=="pause"){
     Game.GameState = "alive";
     window.clearInterval(Game.timing);
     Game.timing = window.setInterval(bindParamsToFun(Game.Snack,Game.Snack.move,Game.Snack.derect),Game.Option.speed);
    }else{
     Game.GameState = "pause";
     window.clearInterval(Game.timing);
    }
   }else if(Game.GameState =="alive"){
    var tempDirect;
    switch (keyCode) {
     case 37:{
      //$("debug").innerHTML +="X";
      tempDirect = -1;
      if(tempDirect!=Game.Snack.derect){
       window.clearInterval(Game.timing);
       Game.timing = window.setInterval(bindParamsToFun(Game.Snack,Game.Snack.move,tempDirect),Game.Option.speed);
      }
      break;
      }
     case 38:{
      //$("debug").innerHTML +="y";
      tempDirect = -2;
      if(tempDirect!=Game.Snack.derect){
       window.clearInterval(Game.timing);
       Game.timing = window.setInterval(bindParamsToFun(Game.Snack,Game.Snack.move,tempDirect),Game.Option.speed);
      }
      break;
      }
     case 39:{
      tempDirect = 1;
      if(tempDirect!=Game.Snack.derect){
       window.clearInterval(Game.timing); 
       Game.timing = window.setInterval(bindParamsToFun(Game.Snack,Game.Snack.move,tempDirect),Game.Option.speed);
      }
      break;
      }
     case 40: {
      tempDirect = 2;
      if(tempDirect!=Game.Snack.derect){
       window.clearInterval(Game.timing);
       Game.timing = window.setInterval(bindParamsToFun(Game.Snack,Game.Snack.move,tempDirect),Game.Option.speed);
      }
      break;
      }
     default :
      break;
    }
   }
  }
 }
}
function bindParamsToFun(obj,fun){
 var args = Array.prototype.slice.call(arguments).slice(2);
 return function(){
 fun.apply(obj,args);
 };
}
function $(id){
 return document.getElementById(id);
}
window.onload = function(){
 Game.GameStart();
 }
//window.onload = function(){
// alert(document.getElementById("theBody"));
//}
</script>
</head>
<body id="theBody">
 <div id="adiv" width="1000" height="1000">
  <div id="info">
   <table>
    <tr>
     <td>关数 :</td>
     <td><span id="act">0</span></td>
    </tr>
    <tr>
     <td>分数 :</td>
     <td><span id="scoure">0</span></td>
    </tr>
   </table>
  </div>
 </div>
</body>