HarmonyOS class-transformer expose注解嵌套对象失效

代码：

import { classToPlain, Expose, plainToClass } from 'class-transformer';
import 'reflect-metadata';
class MyClass {
  @Expose({ name: 'auth-type' })
  authType: number = 1;
  meta: AuthorMeta = new AuthorMeta();
}
class AuthorMeta {
  @Expose({ name: 'focus_count' })
  focusCount: number = 0;
}

let result = plainToClass(MyClass, JSON.parse("{\"auth-type\":3,\"meta\":{\"focus_count\":333} }"))
console.log("focus_countis "+result.meta.focusCount);
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打印结果：focusCount is undefined。

HarmonyOS

superinsect

2024-12-28 08:25:56

3.0w浏览

回答 2

按赞同

按时间

aquaa

对于嵌套的场景，需要将嵌套的类再次通过plainToClass进行转换，如下：

参考代码：

import { classToPlain, Expose, plainToClass } from 'class-transformer';
import 'reflect-metadata';

@Entry
@Component
struct Test6 {
  build() {
    Column(){
      Button('验证1').onClick((event: ClickEvent) => {
        let myClass: MyClass = new MyClass();
        myClass.authType = 1;
        let serializedData = classToPlain(myClass);
        let jsonStr: string = JSON.stringify(serializedData)
        console.log(jsonStr);
        let myClass1: MyClass = JSON.parse(jsonStr)
        let myDataObject = plainToClass(MyClass, myClass1);
        console.log("authType is " + myDataObject.authType);
        let myAuthMeta = plainToClass(AuthorMeta, myDataObject.meta)
        console.log("focusCount is " + myAuthMeta.focusCount);
      })
      Button('验证2').onClick((event: ClickEvent) => {
        let result = plainToClass(MyClass, JSON.parse("{\"auth-type\":3,\"meta\":{\"focus_count\":333}}"))
        let result1 = plainToClass(AuthorMeta, result.meta)
        console.log("focusCount is "+result1.focusCount);
      })
    }
  }
}

class MyClass {
  @Expose({ name: 'auth-type' })
  authType: number = 1;
  meta: AuthorMeta = new AuthorMeta();
}

class AuthorMeta {
  @Expose({ name: 'focus_count' })
  focusCount: number = 0;
}
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2024-12-28 10:20:36

wx580f7e16991cb

import { Expose, plainToClass, Type as JsonType } from "class-transformer"
import "reflect-metadata";

class MaoAppListCOAP {
	@JsonType(() => MaoApp)  
  apps: MaoApp[] = []
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Expose 加上用Type注解就行