javascript - 来自另一个类的 Angular 4 设置属性

Question

我有两个类:

UserInfo

export class UserInfo {
    id: number;
    fullName: string;
    firstName: string;
    lastName: string;
    address: string;
    dob: string
}

用户

import {UserInfo} from './User-Info'

export class User {
    id: number;
    userName: String;
    status: String;
    userInfo: UserInfo;

    constructor(firstName: string, lastName: string, address: string){
        this.userInfo.firstName = firstName;
        this.userInfo.lastName = lastName;
        this.userInfo.address = address;
      }

} 我正在使用 FormGroup 设置数据值:

let user: User = new User(
    this.userForm.controls['firstName'].value,
    this.userForm.controls['lastName'].value,
    this.userForm.controls['address'].value);
this.userService.createUser(user);

我在浏览器上调试:form的值可以获取成功，但是在新建User的时候，报错:

ERROR TypeError: Cannot set property 'firstName' of undefined
    at new User (User.ts:10)

请指教。

Answer 1

你必须像这样初始化你的userInfo变量

userInfo:UserInfo = new UserInfo();

或在构造函数中

constructor(firstName: string, lastName: string, address: string) {
    this.userInfor=new UserInfo();

    this.userInfo.firstName = firstName;
    this.userInfo.lastName = lastName;
    this.userInfo.address = address;
}