That is the exact reason to add the @Injectable() decorator on a service if this service has some dependencies itself. Inside your emailValidator use below code: Inside your component where you want to use ValidationService, inject ValidationService dependency and use below code whereever emailValidator is required. Find centralized, trusted content and collaborate around the technologies you use most. What's the difference between a magic wand and a spell. Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, nice answer smnbbrv, ive decided to change the validator to be a service but its good to explore if there are other options which might come in handy later. First of all, it is simple to pass a Http instance to your static function: where this.http is Http injected into the component. you should not do things like that. The below AppService with dummy decorator and httpService can be injected in AppComponent without any problems. Third, static methods on angular services make nearly no sense. This is because there are no dependency services inside AppService. The document may mislead us about the meaning of the @Injectable decorator. This issue has been automatically locked due to inactivity. Another way. This action has been performed automatically by a bot. $(document).ready equivalent without jQuery. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Announcing the Stacks Editor Beta release! JavaScript front end for Odin Project book library database, Defining series before enumitem list starts. Connect and share knowledge within a single location that is structured and easy to search. Scroll to the top of the page using JavaScript? How to encourage melee combat when ranged is a stronger option. In the end you are writing your own injector. rev2022.7.21.42639. If you want to use angular services (and Http is an angular service) you must inject them as I told above as a constructor attribute to another service / component, which means if you want to use Http you need to have your service injectable. http://plnkr.co/edit/IJVf79C1D8bNVLg9Kh2f?p=preview, The Injectable API documentation is incorrect. Why is the US residential model untouchable and unquestionable? Short story about the creation of a spell that creates a copy of a specific woman. It should be fixed asap. Read more about our automatic conversation locking policy. Thnx! To learn more, see our tips on writing great answers. Well occasionally send you account related emails. A week ago I had a similar problem: passing a service instance to a simple class and passing it directly to the class constructor (first workaround) helped to achieve that. Make the documentation match the actual behavior of angular, or vice-versa. Happens on all environments. The third way is to take a standard Angular injector and try to play around it. Have a question about this project? Service is injectable without Injectable decorator. Sign in First of all, I don't believe this was ever working in RC5. The CLI also adds Injectable to all the services it creates, and the tutorial explains that a service must have this annotation. @Injectable is needed if you want to inject things into a service. Trending is based off of the highest score sort and falls back to it if no posts are trending. Can a human colony be self-sustaining without sunlight using mushrooms? It seems that the Injectable annotation is actually only needed if the service itself has dependencies that must be injected in its constructor, but that doesn't match with what the documentation says. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. How should I deal with coworkers not respecting my blocking off time in my calendar for work? However, a simple experiment with a component using a service not annotated with Injectable works fine (see http://plnkr.co/edit/IJVf79C1D8bNVLg9Kh2f?p=preview for example). This all might work but as a developer I would cry if I would need to support things like that. How does one show this complex expression equals a natural number? Minimal reproduction of the problem with instructions I also hope it helps somebody because sometimes it is useful to know these things. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. But the important thing here is any class that is going to be injected with Angular is decorated. For example, Let's see the different variations of AppService in a root component. Now we can access instance inside static methods and use Http service dynamically. You signed in with another tab or window. So the answer is no, you can't do it in a nice way. Second, if you don't add your class to the injector (you don't pass it as a constructor attribute to another service / component) you should not call it service in angular, although it might be service in your understanding. Could you please check on this ive implemented but getting an error, Using a service without injection in angular2, https://angular.io/docs/ts/latest/api/http/index/Http-class.html, Design patterns for asynchronous API communication. Asking for help, clarification, or responding to other answers. Get selected text from a drop-down list (select box) using jQuery. @jnizet you please open documentation issue at https://github.com/angular/angular.io ? Use the below code inside your ValidationService. Injector will throw NoAnnotationError when trying to instantiate a class that does not have @Injectable marker. What is the difference between "let" and "var"? Already on GitHub? How can I use parentheses when there are math parentheses inside? In constructor we are assigning static instance variable to current instance. How did this note help previous owner of this old film camera? How do I modify the URL without reloading the page? Get selected value in dropdown list using JavaScript. Making statements based on opinion; back them up with references or personal experience. What happens if I accidentally ground the output of an LDO regulator? Thanks for contributing an answer to Stack Overflow! Or the documentation should be fixed to explain what Injectable really is for. The below AppService can be injected in AppComponent without any problems. This is because meta information is generated with dummy decorator. How do I chop/slice/trim off last character in string using Javascript? Please file a new issue if you are encountering a similar or related problem. Inject your class as a service and don't use static methods. Launch this plunkr: http://plnkr.co/edit/IJVf79C1D8bNVLg9Kh2f?p=preview. What is the motivation / use case for changing the behavior? The second workaround is actually very much used for unit testing the services, so this is also helpful. Please tell us about your environment: No. I don't think it's a documentation issue necessarily, you could just as well argue that the decorator is poorly named and should be given a new name like provide. Documentation issue created: angular/angular.io#2546. By clicking Sign up for GitHub, you agree to our terms of service and The text was updated successfully, but these errors were encountered: Yes, the documentation should be fixed. to your account, I'm submitting a (check one with "x"), A marker metadata that marks a class as available to Injector for creation. This is because meta information is generated with Injectable decorator. privacy statement. ```js function SomeDummyDecorator() { return (constructor: Function) => console.log(constructor); }. The .css-uhw1xb{border-radius:var(--chakra-radii-sm);-webkit-padding-start:var(--chakra-space-1);padding-inline-start:var(--chakra-space-1);-webkit-padding-end:var(--chakra-space-1);padding-inline-end:var(--chakra-space-1);font-size:0.875em;padding-top:2px;padding-bottom:2px;white-space:nowrap;line-height:var(--chakra-lineHeights-normal);color:var(--chakra-colors-purple-500);}@Injectable() decorator is not strictly required if the class has other Angular decorators on it or does not have any dependencies. Sign up for a free GitHub account to open an issue and contact its maintainers and the community. If a creature's best food source was 4,000 feet above it, and only rarely fell from that height, how would it evolve to eat that food? Why does hashing a password result in different hashes, each time? Do weekend days count as part of a vacation? angular should throw an error when an injector is trying to create an instance of a service not decorated with Injectable. You can now choose to sort by Trending, which boosts votes that have happened recently, helping to surface more up-to-date answers. NA. Note that FooService is successfully created by the injector and injected into the app component, even though it doesn't have the Injectable decorator. js @Injectable({ providedIn: 'root', }) export class AppService { constructor(http: HttpService) { console.log(http); } }. There is a way by creating singleton static instance. Is it patent infringement to produce patented goods but take no compensation? Tannakian-type reconstruction of etale fundamental group. [] If the service has no injection request in a constructor (does not inject anything) you could simply do. Am new to angular2 and i have a class which has static functions in angular2 and i would like to implement a http request on one of the static functions that is, I have static classes that manage form validation, In my case above how can i use the http in the static function probably by assigning it to a variable, This is being used Here but it was in RC5 whic fails to me. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. i.e, If we add the decorator, the metadata design:paramtypes is added, and the dependency injection can do it's job. and the generated javascript code of above service has meta information about HttpService, js var AppService = (function () { function AppService(http) { console.log(http); } AppService = __decorate([ core_1.Injectable(), __metadata('design:paramtypes', [http_service_1.HttpService]) ], AppService); return AppService; }()); exports.AppService = AppService; The below AppService with @injectable decorator and httpService can be injected in AppComponent without any problems. Skipping a calculus topic (squeeze theorem), Scientifically plausible way to sink a landmass. Yes, there are cases when it might help (service in angular2 might have more than one instance), however I believe this is not your case. Services are easy to create on your own.