继承

[lovelmh13]

// 寄生组合继承
function Father(name) {
  this.name = name
  this.city = '北京'
}

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

function Child(name, age) {
  Father.call(this, name) // 继承属性
  this.age = age
}

// 继承方法 等价于 Child.prototype.__proto__ = Father.prototype
Child.prototype = Object.create(Father.prototype) // 原型链
Child.prototype.constructor = Child // 原型链，注意这里的构造函数是指回 Child

Child.prototype.getAge = function () {
  return this.age
}

var child = new Child('lmh', 25)
var myname = child.getName()
var age = child.getAge()

console.log(myname)
console.log(age)