自定义装饰器的使用问题

// 类装饰器 
function decorateKlass(target: ESObject) { 
  console.log("decorateKlass") 
} 
 
@decorateKlass 
class Person { 
  age: number = 12 
} 
 
// 方法装饰器 
export function MyDescriptor(target: Object, key: string, descriptor: PropertyDescriptor) { 
  const originalMethod: Function = descriptor.value 
  descriptor.value = (...args: Object[]) => { 
    console.log(`Calling ${target.constructor.name} method ${key} with argument: ${args}`) 
    const result: Object = originalMethod(...args) 
    console.log(`Method ${key} returned: ${result}`) 
    return result 
  } 
  return descriptor 
} 
 
@Entry 
@Component 
struct DecoratorDemo { 
  @State message: string = 'Hello World'; 
 
  aboutToAppear() { 
    this.demo() 
  } 
 
  build() { 
    Flex() { 
    } 
    .backgroundColor(Color.Green) 
    .constraintSize({ 
      minWidth: 100, 
      maxWidth: 200, 
      minHeight: 0, 
      maxHeight: 200 
    }) 
    .height('100%') 
  } 
 
  @MyDescriptor 
  demo() { 
    let person = new Person(); 
    return person.age 
  } 
}