javascript - 正确实例化复杂的 JS 对象

Question

我正在通过 Web 服务获取数据，并且想用地址对象填充我的对象 User。

当尝试为对象 this.user.address.residentialAddress 赋值时，我得到了

ERROR TypeError: Cannot set property 'residentialAddress' of undefined

尝试使用构造函数实例化时会出现相同的错误。简单console.log(this.user.address.residentialAddress.City);输出值。

我的猜测是我没有正确创建对象，但我看不到解决方案？

private user: MyUser;
...
this.user = new MyUser();

this.user.address.residentialAddress = {
          City: data.address.residentialAddress.City,
          StreetAddress: data.address.residentialAddress.StreetAddress,
          Suburb: data.address.residentialAddress.Suburb,
          Province: data.address.residentialAddress.Province
};       


export class Address {    
    public StreetAddress: string;
    public Suburb: string;
    public City: string;
    public Province: string;

    constructor(street: string, suburb: string, city: string, province: string){
        this.StreetAddress = street;
        this.Suburb = suburb;
        this.City = city;
        this.Province = province;
    }
}

export class MyUser {    
    address: {
        residentialAddress: Address;
        postalAddress: Address;
    }
    ....

}

Answer 1

我认为你应该将地址放在构造函数中:

export class MyUser {    
    public address: object;
    constructor(){
        this.address = {
            residentialAddress: Address;
            postalAddress: Address;
        }
    }

}

这将使user.address在实例化后被定义，并且Cannot set property 'residentialAddress' of undefined应该消失。