如何通过另一个类访问方法并创建对象

Question

OOP Javascript 新手！ 我有 2 个类，订单和客户。 我有一个方法 getName()。 我希望 customer 作为我在 Order 类中的属性之一。 我已经为两者创建了对象，但似乎无法访问订单对象中的客户名称。

客户.js

class Customer{
constructor(id, name, address,creditCard) {
this._id=id;
this._name=name;
this._address=address;
this._creditCard=creditCard;
}

getName(){
    return this._name;
}
}

订单.js

class Order {
customer;
constructor(id, date) {
  this._id = id;
 this._date=date;

this.customer=new Customer();
}

getNameCustomer() {
  
 return this.customer.getName();
}
 }

数据.js

  const customer1 = new Customer(123,"John","123 E Cookie St",'xxxx xxxx xxxx 1223');

   const order1= new Order(801,'January 12, 2021 01:15:00',customer1.getNameCustomer() );

  let orders=[order1];

Answer 1

您正在调用不存在的customer1上的getNameCustomer方法。 你应该使用

customer1.getName()

但是，如果您在Order类中传递customer对象并将其设为属性，则可以做得更好：

 class Customer { constructor(id, name, address, creditCard) { this._id = id; this._name = name; this._address = address; this._creditCard = creditCard; } getName() { return this._name; } } class Order { constructor(id, date, customer) { this._id = id; this._date = date; this._customer = customer; } getNameCustomer() { return this._customer.getName(); } } const customer1 = new Customer(123, "John", "123 E Cookie St", "xxxx xxxx xxxx 1223"); const order1 = new Order(801, "January 12, 2021 01:15:00", customer1); console.log(order1); console.log(order1.getNameCustomer());

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