angular
Unknown element — component not declared (NG8001)
NG8001.*'([^']+)' is not a known element
Fixes
- 1.Import the module that exports the component into your feature module's imports array
- 2.If standalone component, add it to the `imports` array of the consuming component
- 3.Check the component's selector matches exactly what's in the template (including 'app-' prefix)
templatemodulesdeclarations
Related Errors
angular3 fixes
ExpressionChangedAfterItHasBeenCheckedError (NG0100)
NG0100.*Expression has changed after it was checked
- •Move the value change to ngAfterViewInit with a ChangeDetectorRef.detectChanges() call
- •Use setTimeout(() => { ... }) to defer the change to the next cycle
angular3 fixes
Circular dependency in DI (NG0200)
NG0200.*Circular dependency in DI detected
- •Break the cycle by injecting one service lazily with `@Inject(forwardRef(() => ServiceName))`
- •Extract shared logic into a third service that both services depend on
angular3 fixes
NullInjectorError — missing provider
NullInjectorError: No provider for (\w+)
- •Add the service to the `providers` array of the module or component that needs it
- •Use `@Injectable({ providedIn: 'root' })` on the service class for app-wide singleton