javascript - TypeError：无法读取 es6 模型上未定义的属性“first_name”

Question

我想在 es6 模型中设置 JSON API，但出现此错误 TypeError: Cannot read property 'first_name' of undefined

JSON API：

{
      “类型”：“用户”，
      “身份证”：2，
      “属性”： {
        “用户名”：“madelynn81”，
        “电子邮件”：“[e-mail]”，
        "first_name": "埃米尔",
        "last_name": "Veum",
        “created_at”：“2018-11-17 11:48:13”
      },
      “链接”：{
        “自我”：“http://test.test/api/v1/user/2”
      }
    }

es6模型

class UserModel {
    constructor(data) {
        this.id = data.id;
        this.first_name = data.attributes.first_name;
        this.last_name = data.attributes.last_name;
        this.username = data.attributes.username;
        this.email = data.attributes.email;
        this.created_at = data.attributes.created_at;
        this.link = data.links.self;
    }

    get getId() {
        return this.id;
    }

    set setId(value) {
        this.id = value;
    }

    get getFirstName() {
        return this.first_name;
    }

    set setFirstName(value) {
        this.first_name = value;
    }

    get getLastName() {
        return this.last_name;
    }

    set setLastName(value) {
        this.last_name = value;
    }

    get getUsername() {
        return this.username;
    }

    set setUsername(value) {
        this.username = value;
    }

    get getEmail() {
        return this.email;
    }

    set setEmail(value) {
        this.email = value;
    }

    get getCreatedAt() {
        return this.created_at;
    }

    set setCreatedAt(value) {
        this.created_at = value;
    }

    get getLink() {
        return this.link
    }

    set setLink(value) {
        this.link = value
    }
}

我该如何解决

标签： javascriptjsonecmascript-6

Answer 1

从您的问题中不清楚您如何使用吸气剂来获取价值。一个问题：您的 set/get 对应使用相同的属性名称命名。它们的命名应与持有该值的属性不同。例如：_id用于值属性名称，以及id用于获取/设置名称。

class UserModel {

  constructor(data) {
    this._id = data.id;
    this._firstName = data.attributes.first_name;
  }

  get id() {
    return this.id;
  }

  set id(value) {
    this._id = value;
  }

  get firstName() {
    return this._firstName;
  }

  set firstName(value) {
    this._firstName = value;
  }

}
const data = {
  "type": "user",
  "id": 2,
  "attributes": {
    "username": "madelynn81",
    "email": "[e-mail]",
    "first_name": "Emile",
    "last_name": "Veum",
    "created_at": "2018-11-17 11:48:13"
  },
  "links": {
    "self": "http://test.test/api/v1/user/2"
  }
}

const user = new UserModel(data);
console.log(user.firstName)