HarmonyOS如何实现双向数据绑定

class keyValue{ 
  key:string = '' 
  value:number = 0 
  constructor(key: string, value: number) { 
    this.key = key 
    this.value = value 
  } 
} 
@Entry 
@Component 
struct Test{ 
  @State arr:keyValue[] = [] 
  aboutToAppear(): void { 
    for (let i = 0; i < 10; i++) { 
      this.arr.push(new keyValue(i+"--",i)) 
    } 
  } 
  build() { 
    Column(){ 
      Text('点击按钮，切换第一条数据').onClick(()=>{ 
        this.arr[0] = new keyValue("测试一下", 0) 
      }) 
      Text('点击按钮，切换第二条数据').onClick(()=>{ 
        this.arr[1] = new keyValue("测试两下", 1) 
      }) 
      csComponent({arr:this.arr}) 
    } 
  } 
} 
@Component 
export struct csComponent{ 
  @Link arr:keyValue[] 
  build() { 
    Column(){ 
      ForEach(this.arr, (item:keyValue, index) => { 
        Text(item.key) 
      }, (item:keyValue) => item.key) 
    } 
  } 
}