js常用的继承--组合式继承

 function SuperType(name){
  this.name=name;
  this.colors=["red","blue","green"];
 }
 SuperType.prototype.sayName=function(){
  console.log(this.name);
 }
 function SubType(name,age){
  SuperType.call(this,name);
  this.age=age;
 }
 SubType.prototype=new SuperType();
 SubType.prototype.constructor=SubType;
 SubType.prototype.sayAge=function(){
  console.log(this.age);
 }
 var instance1=new SubType("zxf",24);
 instance1.colors.push("black");
 console.log(instance1.colors);//["red","blue","green","black"]
 instance1.sayName();//"zxf"
 instance1.sayAge();//24
 var instance2=new SubType("jay",36);
 console.log(instance2.colors);//["red","blue","green"]
 instance2.sayName();//"jay"
 instance2.sayAge();//36