Returns an Observable that emits the items you specify as arguments before it begins to emit
items emitted by the source Observable.
startWith<T, D>(...array: Array<T | SchedulerLike>): OperatorFunction<T, T | D>
Parameters
Returns
OperatorFunction<T, T | D>: An Observable that emits the items in the specified Iterable and then emits the items
emitted by the source Observable.
Description
First emits its arguments in order, and then any
emissions from the source.
Examples
Start the chain of emissions with "first", "second"
import { of } from 'rxjs';
import { startWith } from 'rxjs/operators';
of("from source")
.pipe(startWith("first", "second"))
.subscribe(x => console.log(x));
// results:
// "first"
// "second"
// "from source"
Overloads
startWith(scheduler?: SchedulerLike): MonoTypeOperatorFunction<T>
Parameters
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
MonoTypeOperatorFunction<T>
|
startWith(v1: D, scheduler?: SchedulerLike): OperatorFunction<T, T | D>
Parameters
| v1 |
Type: D.
|
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
OperatorFunction<T, T | D>
|
startWith(v1: D, v2: E, scheduler?: SchedulerLike): OperatorFunction<T, T | D | E>
Parameters
| v1 |
Type: D.
|
| v2 |
Type: E.
|
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
OperatorFunction<T, T | D | E>
|
startWith(v1: D, v2: E, v3: F, scheduler?: SchedulerLike): OperatorFunction<T, T | D | E | F>
Parameters
| v1 |
Type: D.
|
| v2 |
Type: E.
|
| v3 |
Type: F.
|
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
OperatorFunction<T, T | D | E | F>
|
startWith(v1: D, v2: E, v3: F, v4: G, scheduler?: SchedulerLike): OperatorFunction<T, T | D | E | F | G>
Parameters
| v1 |
Type: D.
|
| v2 |
Type: E.
|
| v3 |
Type: F.
|
| v4 |
Type: G.
|
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
OperatorFunction<T, T | D | E | F | G>
|
startWith(v1: D, v2: E, v3: F, v4: G, v5: H, scheduler?: SchedulerLike): OperatorFunction<T, T | D | E | F | G | H>
Parameters
| v1 |
Type: D.
|
| v2 |
Type: E.
|
| v3 |
Type: F.
|
| v4 |
Type: G.
|
| v5 |
Type: H.
|
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
OperatorFunction<T, T | D | E | F | G | H>
|
startWith(v1: D, v2: E, v3: F, v4: G, v5: H, v6: I, scheduler?: SchedulerLike): OperatorFunction<T, T | D | E | F | G | H | I>
Parameters
| v1 |
Type: D.
|
| v2 |
Type: E.
|
| v3 |
Type: F.
|
| v4 |
Type: G.
|
| v5 |
Type: H.
|
| v6 |
Type: I.
|
| scheduler |
Optional. Default is undefined.
Type: SchedulerLike.
|
Returns
OperatorFunction<T, T | D | E | F | G | H | I>
|
startWith(...array: Array<D | SchedulerLike>): OperatorFunction<T, T | D>
Parameters
Returns
OperatorFunction<T, T | D>
|