angularJS中对decorator函数的依赖注入

Question

使用angularJS时，可以使用$provide.decorator('thatService',decoratorFn)为服务注册装饰函数。

创建服务实例后，$injector将把它（服务实例）传递给注册的装饰函数，并将该函数的结果用作装饰服务。

现在假设thatService使用它已经注入其中的thatOtherService

我如何获得对thatOtherService的引用，以便能够在我的decoratorFN想要添加到thatService的.myNewMethodForThatService()中使用它？

Answer 1

这取决于确切的用例-需要更多信息才能得到明确的答案
（除非我误解了要求）这里有两种选择：

1） 从ThatService:暴露ThatOtherService

.service('ThatService', function ThatServiceService($log, ThatOtherService) {
  this._somethingElseDoer = ThatOtherService;
  this.doSomething = function doSomething() {
    $log.log('[SERVICE-1]: Doing something first...');
    ThatOtherService.doSomethingElse();
  };
})
.config(function configProvide($provide) {
  $provide.decorator('ThatService', function decorateThatService($delegate, $log) {
    // Let's add a new method to `ThatService`
    $delegate.doSomethingNew = function doSomethingNew() {
      $log.log('[SERVICE-1]: Let's try something new...');
      // We still need to do something else afterwards, so let's use
      // `ThatService`'s dependency (which is exposed as `_somethingElseDoer`)
      $delegate._somethingElseDoer.doSomethingElse();
    };
    return $delegate;
  });
});

2） 在decorator函数中注入ThatOtherService：

.service('ThatService', function ThatServiceService($log, ThatOtherService) {
  this.doSomething = function doSomething() {
    $log.log('[SERVICE-1]: Doing something first...');
    ThatOtherService.doSomethingElse();
  };
})
.config(function configProvide($provide) {
  $provide.decorator('ThatService', function decorateThatService($delegate, $log, ThatOtherService) {
    // Let's add a new method to `ThatService`
    $delegate.doSomethingNew = function doSomethingNew() {
      $log.log('[SERVICE-2]: Let's try something new...');
      // We still need to do something else afterwatds, so let's use
      // the injected `ThatOtherService`
      ThatOtherService.doSomethingElse();
    };
    return $delegate;
  });
});

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在这个演示中，您可以看到这两种方法都在发挥作用。