HarmonyOS 加载本地rowfile文件中的 json 数据， 然后转成对象，怎么实现？

//  a.json 的内容 
{ 
  "a": [ 
    { 
      "name": "module_desc", 
      "value": "module description" 
    }, 
    { 
      "name": "EntryAbility_desc", 
      "value": "description" 
    }, 
    { 
      "name": "EntryAbility_label", 
      "value": "label" 
    } 
  ] } 
//获取rowfile文件并解析成对象 
import { common } from '@kit.AbilityKit'; 
import { BusinessError } from '@kit.BasicServicesKit'; 
import { buffer } from '@kit.ArkTS'; 
//构造对象 
class  TestObj { 
public   a: TestobjOne[]; 
constructor(a: TestobjOne[]) { 
this.a = a; 
} 
} 
class TestobjOne{ 
public   name:string ; 
public   value: string; 
constructor(name:string ,value:string) { 
this.name  = name; 
this.value  = value; 
} 
}
@Entry 
@Component 
struct Index { 
 
  private  context = getContext(this) as common.UIAbilityContext; 
  build() { 
    Column() { 
 
      Button("获取rawFile文件").onClick(()=>{ 
        try { 
          let jsonUti8Arry =   this.context.resourceManager.getRawFileContentSync("a.json"); 
          let JsonStr =  buffer.from(jsonUti8Arry).toString(); 
          let Obj: TestObj  =   JSON.parse(JsonStr) 
          //测试获取TestobjOne对象的name字段 
          console.log(Obj.a[0].name) 
 
        } catch (error) { 
          let code = (error as BusinessError).code; 
          let message = (error as BusinessError).message; 
          console.error(`getRawFileContentSync failed, error code: ${code}, message: ${message}.`); 
        } 
      }) 
    } 
    .width('100%') 
    .height('100%')