HarmonyOS 在ArkTS中，想要将JSON 转为Class后，Class 中的function 方法丢失了

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; 
  } 
} 
 
let json = '{"code":0,"msg":"success"}'; 
let dataBean = DataBean.fromJson(json); 
console.log("test",dataBean.msg); // success 
console.log("test",dataBean.isOK()); // true，