HarmonyOS axios发送网络请求，默认的序列化model会丢失方法和属性？

Question

在使用"@ohos/axios": "2.2.1"发送网络请求时候，指定response的类型是自定义的一个class的model对象，默认的序列化model，除了接口响应返回的属性，在model内部又定义了一些额外属性和方法，但是在使用的时候，额外属性和方法都会丢失无效，该如何处理？

Answer 1

axios自带的默认的序列化，会丢失class实例自定义的方法。

1、可以使用自定义序列化实例方法，如上述示例中的fromJson自定义静态方法，从json字符串创建 dataBean实例。

2、可以使用第三方库class-transformer来实现该功能，地址为：

https://gitee.com/openharmony-tpc/openharmony\_tpc\_samples/tree/master/class-transformer

示例如下：

import { plainToClass } from "class-transformer";

interface UserJson {
  id: number,
  firstName: string,
  lastName: string,
  age: number
}

const userJson: UserJson = {
  id: 1,
  firstName: "Johny",
  lastName: "Cage",
  age: 27
}

class User {
  id: number;
  firstName: string;
  lastName: string;
  age: number;

  constructor() {
    this.id = 0;
    this.firstName = "";
    this.lastName = "";
    this.age = 0;
  }

  getName() {
    return this.firstName + ' ' + this.lastName;
  }

  isAdult() {
    return this.age > 36 && this.age < 60;
  }
}

class DataBean {
  code = -1;
  msg = '';

  isOK() {
    return this.code === 0;
  }

  // 静态方法，从 JSON 字符串创建 DataBean 实例
  static fromJson(jsonString: string): DataBean {
    const jsonData: ESObject = JSON.parse(jsonString);
    const dataBean = new DataBean();
    dataBean.code = jsonData.code;
    dataBean.msg = jsonData.msg;
    return dataBean;
  }
}

@Entry
@Component
struct JSONParseModelPage {
  @State message: string = 'Hello World';

  build() {
    Column() {
      Text(this.message)
        .id('JSONParseModelPageHelloWorld')
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
        .alignRules({
          center: { anchor: '__container__', align: VerticalAlign.Center },
          middle: { anchor: '__container__', align: HorizontalAlign.Center }
        })

      Button() {
        Text('自定义序列化')
      }
      .type(ButtonType.Capsule)
      .height(40)
      .width(200)
      .margin({ top: 20 })
      .onClick(() => {
        let json = '{"code":0,"msg":"success"}';
        let dataBean = DataBean.fromJson(json);
        console.log("test", dataBean.msg); // success
        console.log("test", dataBean.isOK());
      })

      Button() {
        Text('transformer1')
      }
      .type(ButtonType.Capsule)
      .height(40)
      .width(200)
      .margin({ top: 20 })
      .onClick(() => {
        const user: User = plainToClass(User, userJson);
        console.log("test", user.getName());
      })

      Button() {
        Text('transformer2')
      }
      .type(ButtonType.Capsule)
      .height(40)
      .width(200)
      .margin({ top: 20 })
      .onClick(() => {
        let userStr = '{"id":2,"firstName":"Tom","lastName": "Jerry","age": 27}'
        let userJson1: UserJson = JSON.parse(userStr)
        const user: User = plainToClass(User, userJson1);
        console.log("test", user.getName());
      })
    }
    .height('100%')
    .width('100%')
  }
}