Recently, I encountered an error while working with angular services related to the use of BehaviorSubject.
The Error
A message stating that 'Module "ng5/node_modules/rxjs/BehaviorSubject" has no exported member 'BehaviorSubject'' appeared.
data.service.ts
import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs/BehaviorSubject';
@Injectable()
export class DataService {
constructor() { }
}
When importing all of RxJS, simply use the following code:
import { BehaviorSubject } from 'rxjs';
If you only require BehaviorSubject specifically:
import { BehaviorSubject } from 'rxjs/internal/BehaviorSubject';
Additional Explanation:
In ES6 / TypeScript, every import statement is connected to the export keyword. When you navigate to node_modules/rxjs/index.d.ts, you can view all the classes that are exported.
This implies that anything listed as exported in this file can be imported using:
import { SomeThing } from 'rxjs';However, your final bundled file will include the entire RxJS library, even parts that may not be necessary.
To prevent this, it is recommended to import from: from 'rxjs/internal/SomeThing' (replace SomeThing with what you specifically need)
For operators, they can be found at:
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