HarmonyOS 在一个class类中封装了多个方法，如何才能动态的去调用这些方法呢？

export class dddd { 
  fun : Record<string, Function> = {}; 
  constructor() { 
    this.fun={'ssss':this.ddd1,'sdss':this.ccc} 
  } 
  ddd1(){ 
    console.log('ddd1') 
  } 
  ccc(){ 
    console.log('cccc') 
  } 
}

import display from '@ohos.display'; 
import { dddd } from './FunTest'; 
@Entry 
@Component 
struct DisplayTest { 
  private ddd : dddd = new dddd() 
  build() { 
    Column({space:20}){ 
      Button('Test') 
        .type(ButtonType.Capsule) 
        .onClick(() => { 
          this.ddd.fun['ssss']() 
          this.ddd.fun['sdss']() 
        }) 
        .width('50%') 
    } 
    .width("100%") 
    .height('100%') 
    .justifyContent(FlexAlign.Center) 
  } 
}