返回一个 Observable，它在开始发出源 Observable 发出的项目之前，发出您指定为参数的项目。

startWith<T, D>(...array: (SchedulerLike | T)[]): OperatorFunction<T, T | D>

参量

returns

OperatorFunction<T, T | D>：一个 Observable，它发出指定的 Iterable 中的项目，然后发出由源 Observable 发出的项目。

描述

首先按顺序发出其参数，然后从源发出任何信号。

例子

从开始排放链"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"

超载

startWith(scheduler: SchedulerLike): MonoTypeOperatorFunction<T>

returnsMonoTypeOperatorFunction<T>

startWith(v1: D, scheduler: SchedulerLike): OperatorFunction<T, T | D>

returnsOperatorFunction<T, T | D>

startWith(v1: D, v2: E, scheduler: SchedulerLike): OperatorFunction<T, T | D | E>

returnsOperatorFunction<T, T | D | E>

startWith(v1: D, v2: E, v3: F, scheduler: SchedulerLike): OperatorFunction<T, T | D | E | F>

returnsOperatorFunction<T, T | D | E | F>

startWith(v1: D, v2: E, v3: F, v4: G, scheduler: SchedulerLike): OperatorFunction<T, T | D | E | F | G>

returnsOperatorFunction<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>

returnsOperatorFunction<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>

returnsOperatorFunction<T, T | D | E | F | G | H | I>

startWith(v1: D): OperatorFunction<T, T | D>

returnsOperatorFunction<T, T | D> startWith(v1: D, v2: E): OperatorFunction<T, T | D | E>

returnsOperatorFunction<T, T | D | E>

startWith(v1: D, v2: E, v3: F): OperatorFunction<T, T | D | E | F>

returnsOperatorFunction<T, T | D | E | F>

startWith(v1: D, v2: E, v3: F, v4: G): OperatorFunction<T, T | D | E | F | G>

returnsOperatorFunction<T, T | D | E | F | G>

startWith(v1: D, v2: E, v3: F, v4: G, v5: H): OperatorFunction<T, T | D | E | F | G | H>

returnsOperatorFunction<T, T | D | E | F | G | H>

startWith(v1: D, v2: E, v3: F, v4: G, v5: H, v6: I): OperatorFunction<T, T | D | E | F | G | H | I>

returnsOperatorFunction<T, T | D | E | F | G | H | I>

startWith(...array: D[]): OperatorFunction<T, T | D>

returnsOperatorFunction<T, T | D>

startWith(...array: (SchedulerLike | D)[]): OperatorFunction<T, T | D>

returnsOperatorFunction<T, T | D>