Class BehaviorSubject<Data>

Represents a BehaviorSubject that extends the Subject class and provides the functionality of an observable and an observer.

Type Parameters

  • Data = any

    The type of the data that the BehaviorSubject holds.

Hierarchy (View Summary)

Implements

Observables

operator

Other

constructor data debounce delay filter flatMap map mapAsync merge next once reduce repeat split subscribe tap toIteratorContext toObserver toPromise unsubscribeAll

Observables

operator

operator: <T = any>(
    callbackfn: (value: TObserver<Data>) => TObserver<T>,
) => TObserver<T>

Applies a callback function to the values emitted by an observer.

Type declaration

Other

constructor

data

debounce

debounce: (delay?: number) => TObserver<Data>

Creates a debounced observer with an optional delay.

Type declaration

    • (delay?: number): TObserver<Data>

    • Parameters

      • Optionaldelay: number

        The delay in milliseconds before emitting the data.

      Returns TObserver<Data>

      • The debounced observer.

delay

delay: (delay?: number) => TObserver<Data>

Creates a delayed observer with an optional delay.

Type declaration

    • (delay?: number): TObserver<Data>

    • Parameters

      • Optionaldelay: number

        The delay in milliseconds before emitting the data.

      Returns TObserver<Data>

      • The delayed observer.

filter

filter: (callbackfn: (value: Data) => boolean) => TObserver<Data>

Applies a filtering function to the observer and returns a new observer with filtered values.

Type declaration

    • (callbackfn: (value: Data) => boolean): TObserver<Data>

    • Parameters

      • callbackfn: (value: Data) => boolean

        A function that tests each value in the observer. Should return true or false.

      Returns TObserver<Data>

      • A new observer with filtered values.

flatMap

flatMap: <T = any>(callbackfn: (value: Data) => T[]) => TObserver<T>

Applies a transformation function to each value emitted by the observer and flattens the result into a single observer.

Type declaration

    • <T = any>(callbackfn: (value: Data) => T[]): TObserver<T>

    • Type Parameters

      • T = any

        The type of values emitted by the observer.

      Parameters

      • callbackfn: (value: Data) => T[]

        The transformation function to apply to each value emitted by the observer.

      Returns TObserver<T>

      • The observer that emits the flattened values.

map

map: <T = any>(callbackfn: (value: Data) => T) => TObserver<T>

Maps the values of the observer using the given callback function.

Type declaration

    • <T = any>(callbackfn: (value: Data) => T): TObserver<T>

    • Type Parameters

      • T = any

        The type of the mapped values.

      Parameters

      • callbackfn: (value: Data) => T

        A function that maps each value of the observer.

      Returns TObserver<T>

      • An observer with the mapped values.

mapAsync

mapAsync: <T = any>(
    callbackfn: (value: Data) => Promise<T>,
    fallbackfn?: (e: Error) => void,
) => TObserver<T>

Asynchronously maps the emitted values of the observer using the provided callback function.

Type declaration

    • <T = any>(
          callbackfn: (value: Data) => Promise<T>,
          fallbackfn?: (e: Error) => void,
      ): TObserver<T>

    • Type Parameters

      • T = any

        The type of the mapped values.

      Parameters

      • callbackfn: (value: Data) => Promise<T>

        The callback function that maps the emitted values of the observer.

      • Optionalfallbackfn: (e: Error) => void

        The optional fallback function that handles errors during mapping.

      Returns TObserver<T>

      • Returns a new observer that emits the mapped values.

merge

merge: <T = any>(observer: TObserver<T>) => TObserver<Data | T>

Merges the provided observer with the current observer instance. Returns a new observer that emits values from both observers.

Type declaration

next

next: (data: Data) => Promise<void>

Sets the given data and calls the next method of the super class asynchronously.

Type declaration

    • (data: Data): Promise<void>

    • Parameters

      • data: Data

        The data to be set.

      Returns Promise<void>

      Resolves when super class's next method is called.

once

once: (callback: Function) => () => void

Executes the provided callback function only once. The callback function will be invoked when the specified event occurs for the first time.

Type declaration

    • (callback: Function): () => void

    • Parameters

      • callback: Function

        The function to be executed only once.

      Returns () => void

      • A function that removes the registered event listener.

reduce

reduce: <T = any>(
    callbackfn: (acm: T, cur: Data) => T,
    begin: T,
) => TObserver<T>

Applies a reducer function to each value emitted by the observer and returns a single accumulated value.

Type declaration

    • <T = any>(callbackfn: (acm: T, cur: Data) => T, begin: T): TObserver<T>

    • Type Parameters

      • T = any

        The type of the accumulated value and emitted values

      Parameters

      • callbackfn: (acm: T, cur: Data) => T

        A function that accepts the accumulated value and the current emitted value, and returns the new accumulated value

      • begin: T

        The initial value for the accumulator

      Returns TObserver<T>

      • An observer that emits the accumulated value when the original observer completes

repeat

repeat: (interval?: number) => TObserver<Data>

Creates an observer that repeats emitting values at a specified interval.

Type declaration

    • (interval?: number): TObserver<Data>

    • Parameters

      • Optionalinterval: number

        The time interval at which to repeat emitting values.

      Returns TObserver<Data>

      • The created observer.

split

split: () => Observer<
    readonly (
        Data extends readonly InnerArr[]
            ? InnerArr extends readonly InnerArr[]
                ? InnerArr extends readonly InnerArr[]
                    ? InnerArr extends readonly InnerArr[]
                        ? InnerArr extends readonly InnerArr[]
                            ? InnerArr extends readonly InnerArr[]
                                ? InnerArr extends readonly (...)[]
                                    ? (...) extends (...) ? (...) : (...)
                                    : InnerArr
                                : InnerArr
                            : InnerArr
                        : InnerArr
                    : InnerArr
                : InnerArr
            : Data
    )[],
>

Splits the observed data into batches of arrays.

Type declaration

    • (): Observer<
          readonly (
              Data extends readonly InnerArr[]
                  ? InnerArr extends readonly InnerArr[]
                      ? InnerArr extends readonly InnerArr[]
                          ? InnerArr extends readonly InnerArr[]
                              ? InnerArr extends readonly InnerArr[]
                                  ? InnerArr extends readonly InnerArr[]
                                      ? InnerArr extends readonly (...)[]
                                          ? (...) extends (...) ? (...) : (...)
                                          : InnerArr
                                      : InnerArr
                                  : InnerArr
                              : InnerArr
                          : InnerArr
                      : InnerArr
                  : Data
          )[],
      >

    • Returns Observer<
          readonly (
              Data extends readonly InnerArr[]
                  ? InnerArr extends readonly InnerArr[]
                      ? InnerArr extends readonly InnerArr[]
                          ? InnerArr extends readonly InnerArr[]
                              ? InnerArr extends readonly InnerArr[]
                                  ? InnerArr extends readonly InnerArr[]
                                      ? InnerArr extends readonly (...)[]
                                          ? (...) extends (...) ? (...) : (...)
                                          : InnerArr
                                      : InnerArr
                                  : InnerArr
                              : InnerArr
                          : InnerArr
                      : InnerArr
                  : Data
          )[],
      >

      • The observer that emits batches of arrays.

subscribe

subscribe: (callback: Function) => () => void

Subscribes to an event.

Type declaration

    • (callback: Function): () => void

    • Parameters

      • callback: Function

        The callback function to be invoked when the event is triggered.

      Returns () => void

      • A function to unsubscribe from the event.

tap

tap: (callbackfn: (value: Data) => void) => TObserver<Data>

The tap function allows you to perform side effects without modifying the observed data.

toIteratorContext

toIteratorContext: () => {
    done(): void;
    iterate(): AsyncGenerator<Data, void, unknown>;
}

Converts the current object to an iterator context.

Type declaration

    • (): { done(): void; iterate(): AsyncGenerator<Data, void, unknown> }

    • Returns { done(): void; iterate(): AsyncGenerator<Data, void, unknown> }

      The iterator context representing the current object.

Function

toObserver

toObserver: () => TObserver<Data>

Creates a new observer.

Type declaration

toPromise

toPromise: () => Promise<Data>

Converts an observer-based asynchronous operation into a promise-based asynchronous operation.

Type declaration

    • (): Promise<Data>

    • Returns Promise<Data>

      A promise representing the completion or failure of the asynchronous operation.

Function

toPromise

Instance

unsubscribeAll

unsubscribeAll: () => void

Unsubscribes all event listeners.

Type declaration

    • (): void

    • Returns void

      • No return value.

Function

unsubscribeAll

Instance

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