Aspect工具装饰器的使用示例

1、 对类 
util.Aspect.addBefore(EntryAbility, “onCreate”, false, (instance: EntryAbility, want: Want): void => { 
  let params = want.parameters as Record<string, Object>; 
  console.error('testtag 获取pid: '+params[‘ohos.aafwk.param.callerPid’]); 
}); 
 
2、 异步 
 
class Test { 
  static data:string = ‘initData’ 
  static async printData(arg: string) { // 异步方法 
    console.log(‘execute original printData’); 
    console.log('Test.data is ’ + Test.data); 
    console.log(arg); 
    return 0; 
  } 
} 
// 插桩 
util.Aspect.addBefore(Test, “printData”, true, 
(classObj: Object, arg: string): void => { 
  console.log(“execute before”); 
  Reflect.set(classObj, “data”, “dataChangedByBefore”); 
  console.log("arg is " + arg); 
} 
); 
 
Test.printData(“m1”).then((res) => { 
  console.log("res = " + res.toString()); 
  console.log("Test.data = " + Test.data); 
})