04.对象和原型

 

 

 

 

 

 

            function User(name,passwordHash){
                this.name=name;
                this.passwordHash=passwordHash;
                this.toString=function(){
                    return "[User "+this.name+"]";
                }
                this.checkPassword=function(password){
                    return hash(password)===this.passwordHash;
                }
            }

            function CSVReader(separators) {
                this.separators = separators || [","];
                this.regexp = new RegExp(this.separators.map(function(sep) {
                    return "\" + sep[0];
                }).join("|"));
            }

 

            CSVReader.prototype.read=function(str){
                var lines=str.trim().split(/
/);
                return lines.map(function(line){
                    return line.split(this.regexp);//wrong this
                });
            };
            
            var reader=new CSVReader();
            reader.read("a,b,c
d,e,f
");//[["a,b,c"],["d,e,f"]]

            CSVReader.prototype.read=function(str){
                var lines=str.trim().split(/
/);
                return lines.map(function(line){
                    return line.split(this.regexp);
                },this);//forward outer this-binding to callback
            };
            
            var reader=new CSVReader();
            reader.read("a,b,c
d,e,f
");//[["a,b,c"],["d,e,f"]]

            CSVReader.prototype.read=function(str){
                var lines=str.trim().split(/
/);
                var self=this;
                return lines.map(function(line){
                    return line.split(self.regexp);
                });
            };
            
            var reader=new CSVReader();
            reader.read("a,b,c
d,e,f
");//[["a,b,c"],["d,e,f"]]

            CSVReader.prototype.read=function(str){
                var lines=str.trim().split(/
/);
                return lines.map(function(line){
                    return line.split(this.regexp);
                }.bind(this));//bind to outer this-binding
            };
            
            var reader=new CSVReader();
            reader.read("a,b,c
d,e,f
");//[["a,b,c"],["d,e,f"]]

 

            function Scene(context, width, height, images) {
                this.context = context;
                this.width = width;
                this.height = height;
                this.images = images;
                this.actors = [];
            }

            Scene.prototype.register = function(actor) {
                this.actors.push(actor);
            }

            Scene.prototype.unregister = function(actor) {
                var i = this.actors.indexOf(actor);
                if(i >= 0) {
                    this.actors.splice(i, 1);
                }
            };
            Scene.prototype.draw = function() {
                this.context.clearRect(0, 0, this.width, this.height);
                for(var a = thisactors, i = 0, n = a.length; i < n; i++) {
                    a[i].draw();
                }
            }

            function Actor(scene,x,y){
                this.scene=scene;
                this.x=x;
                this.y=y;
                scene.register(this);
            }

            Actor.prototype.moveTo = function(x, y) {
                this.x = x;
                this.y = y;
                this.scene.draw();
            }

            Actor.prototype.exit=function(){
                this.scene.unregister(this);
                this.scene.draw();
            }

            Actor.prototype.draw=function(){
                var image=this.scene.images[this.type];
                this.scene.context.drawImage(imgae,this.x,this.y);
            }

            Actor.prototype.width = function() {
                return this.scene.images[this.type].width;
            }
            Actor.prototype.height = function() {
                return this.scene.images[this.type].height;
            }

 

            function Actor(scene,x,y){
                this.scene=scene;
                this.x=x;
                this.y=y;
                this.id=++Actor.nextID;
                scene.register(this);
            }
            Actor.nextID=0;

            function Alien(scene, x, y, direction, speed, strength) {
                Actor.call(this, scene, x, y);
                this.direction = direction;
                this.speed = speed;
                this.strength = strength;
                this.damage = 0;
                this.id = ++Alien.nextID; //conflicts with actor id!
            }
            Alien.nextID = 0;