在Javascript中定义类

1.使用工厂函数

//工厂函数function Animal(name,type){    animal = {};    animal.name = name;    animal.type = type;    return animal;    }

用new关键字创建类的实例：

var animal1 = new Animal("Andy","dog");console.log(animal1); //Object {name: "Andy", type: "dog"}var animal2 = new Animal();animal2.name = "Tom"; animal2.type = "cat";console.log(animal2); //Object {name: "Tom", type: "cat"}

2.使用构造函数

//构造函数function People(name,gender) {　　　　    this.name = name;　　    this.gender = gender;}

还可以给构造函数的prototype对象定义实例的方法：

People.prototype.add = function(that){    return new People(this.name+" "+that.name,this.gender+" "+that.gender);}

接下来创建该类的实例：

var people1 = new People("Jim","boy");　　console.log(people1); //People {name: "Jim", gender: "boy"}var people2 = new People();　people2.name = "Lucy";people2.gender = "girl";　console.log(people2);//People {name: "Lucy", gender: "girl"}

当然可以调用上面定义的add方法：

var people3 = people1.add(people2);console.log(people3);//People {name: "Jim Lucy", gender: "boy girl"}