HarmonyOS 鸿蒙Next项目中如何使用class-transformer库（npm库）？或在oh仓库中有哪些推荐的json转类对象的库？

class-transformer库已迁移至ohpm中，可直接使用命令 ohpm i class-transformer 安装

import { classToPlain, plainToClass } from 'class-transformer';
@Entry
@Component
struct Index {
  @State message: string = 'Hello World';

  aboutToAppear(): void {
    let user = new User(101, "aaa", "bbb");
    let userJson = classToPlain(user);
    console.log("TEST== userJson = " + 
    JSON.stringify(userJson));
    let userObj: User = plainToClass(User, userJson);
    console.log('TEST== UserObj = ', JSON.stringify(userObj));
  }
  build() {
    Row() {
      Column() {
        Text(this.message)
          .fontSize(50)
          .fontWeight(FontWeight.Bold)
      }
      .width('100%')
    .height('100%')
  }
}

class User {
  id: number;
  firstName: string;
  lastName: string;
  constructor(id: number, firstName: string, lastName: string) {
    this.id = id;
    this.firstName = firstName;
    this.lastName = lastName;
  }
}

更多用法请参考：https://github.com/typestack/class-transformer