testbed.get 和 Angular 2/Jasmine 测试中的注入有什么区别？

Question

I am new to Angular 2 testing. I am trying to figure out what is the difference in using testsbed.get() and just using inject at the test level.

eg:

beforeEach(() => {
    TestBed.configureTestingModule({
        providers: [SomeService]
    });

    const testbed = getTestBed();
    someService= testbed.get(SomeService);
  });
});

vs

it('test service', inject([SomeService], (someService: SomeService) => {

Answer 1

Just to add to the existing answer and if like me you found this question because you are wondering what the difference is between TestBed.get() and TestBed.inject() which I know was not quite what the OP originally asked but it is relevant and is very much related.

I thought it was worth posting that according to the latest Angular documentation that TestBed.inject() is the type safe replacement of TestBed.get() .

From the Angular documentation on TestBed that can be found here .

Answer 2

inject helper function was historically used since AngularJS as an alternative to direct injector calls. In Angular 1, it was necessary to bootstrap a test with ngMock . It is entirely optional in Angular 2 and higher and is just a suggested way for DI in TestBed tests.

It a convenience wrapper for testBed.get that allows to avoid multiple testBed.get calls, similarly to:

const [foo, bar] = [Foo, Bar].map(TestBed.get);

Other helper functions can be optionally used in conjunction with inject , namely async and fakeAsync .

Answer 3

These use to be equivalent, but in Angular 9 the preferred method was updated.

TestBed.get() is deprecated in Angular 9+, and TestBed.inject() is now the preferred type-safe way to inject a dependency.

Read the documentation for clarity: TestBed.get() and TestBed.inject() . The change is one of deprecation.