原型链继承

function Parent() {
  this.name = 'p';
}

Parent.prototype.getName = function() {
  return this.name;
};

function Child() {

}

Child.prototype = new Parent();
Child.prototype.constructor = Child;

构造函数继承

function Child1() {
  Parent.call(this, 'p');

组合式继承

function Parent2(name) {
  this.name = [name];
}
Parent.prototype.getName = function() {
  return this.name;
};
function Child2() {
  // 构造函数继承
  Parent2.call(this, 'zhangsan');
}

原型链继承

Child2.prototype = new Parent2();
Child2.prototype.constructor = Child2;

寄生式组合继承

function Parent3(name) {
  this.name = [name];
}
Parent.prototype.getName = function() {
  return this.name;
};
function Child3() {
  // 构造函数继承
  Parent3.call(this, 'zhangsan');
}

原型链继承

// Child3.prototype = new Parent();
Child3.prototype = Object.create(Parent.prototype) ;  //将`指向父类实例`改为`指向父类原型`
Child3.prototype.constructor = Child3;

//测试
const child1 = new Child();
const child2 = new Child();
child1.name[0] = 'foo';
console.log(child1.name);          // ['foo']
console.log(child2.name);          // ['zhangsan']
child2.getName();                  // ['zhangsan']