javascript 组合按键事件监听实现代码

<script type="text/javascript"> 
   (function(){ 
    /** 
    *dqkeys v1.0.0 | (c) 2016 www.findme.wang 
    *@params json keys 监听的按键 
    *@params bool isorder 按键是否有相应的顺序 
    *@params function sucfuc 完成按键的回调函数 
    *@params function cancelfuc 完成按键取消后的回调函数 
    *@author lidequan 
    */ 
    var dqkeys = function(keys,isorder,sucfuc,cancelfuc) { 
      // 函数体 
      return new dqkeys.fn.init(keys,isorder,sucfuc,cancelfuc); 
    } 
    dqkeys.fn = dqkeys.prototype = { 
      'version':'1.0.0',  //版本号 
      'author':'lidequan', //作者 
      'rightkeys':{},   //监听的按键{key:code},code为按键对应的ascii码  
      'curkeys':[],    //当前按下的键 
      'sucfuc':null,    //完成按键的回调函数 
      'cancelfuc':null,  //完成按键取消后的回调函数 
      'isfinsh':false,  //判断是否完成按键 
      'isorder':false,  //按键是否有相应的顺序 
      init:function(keys,isorder,sucfuc,cancelfuc){ 
        this.rightkeys=keys; 
        this.sucfuc=sucfuc; 
        this.cancelfuc=cancelfuc; 
        this.isorder=isorder; 
          
        return this; 
      }, 
      listenkeys:function(){//监听用户键盘操作         
        var _self=this; 
        _self.addlistener('keydown', function(oevent){ 
          var oevent =oevent || window.event; 
          if(!_self.arraycontain(_self.curkeys,oevent.keycode)){ 
            if(_self.isorder && _self.getnextkey() == oevent.keycode){ 
              _self.curkeys.push(oevent.keycode); 
            }else if(!_self.isorder){ 
              _self.curkeys.push(oevent.keycode); 
            } 
          } 
          if(_self.checkresult(_self.rightkeys,_self.curkeys)){ 
            if(_self.sucfuc && !_self.isfinsh){ 
              _self.sucfuc(); 
            } 
            _self.isfinsh=true; 
          } 
        }); 
        _self.addlistener('keyup', function(oevent){ 
          var oevent =oevent || window.event;          
          if(_self.checkresult(_self.rightkeys,_self.curkeys) && _self.isfinsh){    
            //完成按键,又取消的事件 
            if(_self.cancelfuc){ 
              _self.cancelfuc(); 
            } 
          } 
  
          _self.curkey=_self.remove(_self.curkeys,oevent.keycode); 
          _self.isfinsh=false; 
        }); 
      }, 
      arraycontain:function(arr,val){//判断数组中是否包含某个元素 
          return (arr.indexof(val) == -1) ? false:true; 
      }, 
      checkresult:function(json,arr){ //判断用户是否按下监听的所有按键 
        for(var i in json){ 
           if(arr.indexof(json[i])==-1){ 
             return false; 
           } 
         } 
        return true; 
      }, 
      remove:function(arr,val) { //从数组中移除某个元素       
        var index = arr.indexof(val);  
        if (index > -1) {  
          arr.splice(index, 1);  
        }  
        return arr; 
      }, 
      getnextkey:function(){ //获取下一次按键对应的ascii码 
        for(var i in this.rightkeys){ 
          if(this.curkeys.indexof(this.rightkeys[i])==-1){ 
             return this.rightkeys[i]; 
           } 
        } 
        return null; 
      }, 
      addlistener:function(ev,fn,bool){ //事件绑定 
        if (document.attachevent) {  
          document.attachevent('on' + ev, fn);  
        }else{   
          document.addeventlistener(ev,fn,bool);  
        }  
      } 
  
    } 
    dqkeys.fn.init.prototype = dqkeys.fn; 
    window.dqkeys = window.$$= dqkeys; 
   })(); 
  
  //1.测试 
  dqkeys({'a':65,'b':66},true,function(){ 
                  console.log('okey'); 
                },function(){ 
                  console.log('cancel'); 
                }).listenkeys(); 
  
  //2.测试 
  var dqkeys=new $$({'c':67,'d':68},false,function(){ 
                  console.log('keys down '); 
                },function(){ 
                  console.log('keys cancel'); 
                }); 
  dqkeys.listenkeys(); 
  </script>