细节：js 对象继承的几种模式举例

摘要：原型链继承借用构造函数伪造对象，经典继承无参数有参数组合继承伪经典继承无参数有参数寄生组合式继承引用类型最理想的范式或者可以把函数写成下面这样原型式继承用于共享引用类型的值，与寄生式类似传统版先定义函数，再继承版直接用，再继承省略了定义函数

function Person(){};

Person.prototype = {
    constructor: Person,
    name: "Oliver"
};
        
function People(){};

People.prototype = new Person();
People.prototype.constructor = People;
People.prototype.sayName = function(){
    return this.name;
};

var ins = new People();

console.log(ins.sayName());

function SuperType(){
    this.color = ["red","yellow","white"];
}
function SubType(){
    SuperType.call(this);
}

var instance1 = new SubType();
var instance2 = new SubType();

instance1.color.pop();
console.log(instance1.color); //["red", "yellow"]
console.log(instance2.color); //["red", "yellow", "white"]

function SuperType(name){
    this.name = name;
    this.number = [21,32,14,1];
}
function SubType(name,age){
    SuperType.call(this,name);
    this.age = age;
}

var instance1 = new SubType("Oliver",18);
var instance2 = new SubType("Troy",24);

instance2.number.pop();

console.log(instance1.name + instance1.age + instance1.number); //Oliver1821,32,14,1
console.log(instance2.name + instance2.age + instance2.number); //Troy2421,32,14

function SuperType(){
    this.color = ["red","yellow","white"];
}
SuperType.prototype.sayColor = function(){
    return this.color;
};

function SubType(){
    SuperType.call(this);
    this.number = 321;
}
SubType.prototype = new SuperType();
SubType.prototype.constructor = SubType;
SubType.prototype.sayNumber = function(){
    return this.number;
};

var instance1 = new SubType();
var instance2 = new SubType();

instance2.color.pop();
console.log(instance1.color + instance1.number); //red,yellow,white321
console.log(instance2.color + instance2.number); //red,yellow321

function SuperType(name){
    this.name = name;
    this.number = [32,1342,11,1];
}
SuperType.prototype.sayName = function(){
    return 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(){
    return this.age;
};

var instance1 = new SubType("Oliver",18);
var instance2 = new SubType("Troy",24);

instance2.number.pop();
console.log(instance1.sayName() + instance1.sayAge() + instance1.number); //Oliver1832,1342,11,1
console.log(instance2.sayName() + instance2.sayAge() + instance2.number); //Troy2432,1342,11

function inheritPrototype(subType,superType){
    var prototype = Object(superType.prototype);
    prototype.constructor = subType;
    subType.prototype = prototype;
}

function SuperType(name){
    this.name = name;
    this.number = [321,321,43];
}
SuperType.prototype.sayName = function(){
    return this.name;
};

function SubType(name,age){
    SuperType.call(this,name);
    this.age = age;
}
inheritPrototype(SubType,SuperType);
SubType.prototype.sayAge = function(){
    return this.age;
};

var instance1 = new SubType("Oliver",18);
var instance2 = new SubType("Troy",24);
instance2.number.pop();

console.log(instance1.sayName() + instance1.sayAge() + instance1.number); //Oliver18321,321,43
console.log(instance2.sayName() + instance2.sayAge() + instance2.number); //Troy24321,321

或者可以把inheritPrototype 函数写成下面这样：

function inheritPrototype(SubType,SuperType){
    SubType.prototype = new SuperType();
    SubType.prototype.constructor = SubType;
}

function object(o){
    function F(){};
    F.prototype = o;
    return new F();
}

var SuperType = {
    name: "Oliver",
    number: [321,321,4532,1]
};

var SubType1 = object(SuperType);
var SubType2 = object(SuperType);

SubType1.name = "Troy";
SubType1.number.pop();

SubType2.name = "Alice";
SubType2.number.pop();

console.log(SubType1.name + SubType2.name + SubType1.number + SubType2.number + SuperType.name + SuperType.number); //TroyAlice321,321321,321Oliver321,321

var SuperType = {
    name: "Oliver",
    number: [321,321,4532,1]
};

var SubType1 = Object.create(SuperType); //省略了定义object()函数
var SubType2 = Object.create(SuperType);

SubType1.name = "Troy";
SubType1.number.pop();

SubType2.name = "Alice";
SubType2.number.pop();

console.log(SubType1.name + SubType2.name + SubType1.number + SubType2.number + SuperType.name + SuperType.number); //TroyAlice321,321321,321Oliver321,321

var SuperType = {
    name: "Oliver",
    number: [321,321,4532,1]
};

var SubType1 = Object.create(SuperType,{
    name: {
        value : "Troy"
    }
});
var SubType2 = Object.create(SuperType,{
    name: {
        value : "Alice"
    }
});

SubType1.number.pop();
SubType2.number.pop();

console.log(SubType1.name + SubType2.name + SubType1.number + SubType2.number + SuperType.name + SuperType.number); //TroyAlice321,321321,321Oliver321,321

function createAnother(original){
    var clone = Object(original);
    clone.sayHi = function(){
        return "Hi";
    };
    return clone;
}

var person = {
    name: "Oliver",
    number: [13,21,31,1]
};

var anotherPerson = createAnother(person);
anotherPerson.number.pop();

console.log(anotherPerson.sayHi() + anotherPerson.number); //Hi13,21,31
console.log(person.number); //13,21,31