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 full)

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>(callbackfn): TObserver<T>

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

    Type Parameters

    • T = any

      The type of values emitted by the observer.

    Parameters

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

      The callback function to apply to the emitted values.

        • (value): TObserver<T>

        • Parameters

          • value: TObserver<Data>

          Returns TObserver<T>

    Returns TObserver<T>

    • An observer with the applied operator.

Other

constructor

data

  • get data(): null | Data

  • Retrieves the data stored in the instance.

    Returns null | Data

    The data stored in the instance.

debounce

  • debounce(delay?): TObserver<Data>

  • Creates a debounced observer with an optional delay.

    Parameters

    • Optionaldelay: number

      The delay in milliseconds before emitting the data.

    Returns TObserver<Data>

    • The debounced observer.

delay

  • delay(delay?): TObserver<Data>

  • Creates a delayed observer with an optional delay.

    Parameters

    • Optionaldelay: number

      The delay in milliseconds before emitting the data.

    Returns TObserver<Data>

    • The delayed observer.

filter

  • filter(callbackfn): TObserver<Data>

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

    Parameters

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

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

        • (value): boolean

        • Parameters

          Returns boolean

    Returns TObserver<Data>

    • A new observer with filtered values.

flatMap

  • flatMap<T>(callbackfn): TObserver<T>

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

    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.

        • (value): T[]

        • Parameters

          Returns T[]

    Returns TObserver<T>

    • The observer that emits the flattened values.

map

  • map<T>(callbackfn): TObserver<T>

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

    Type Parameters

    • T = any

      The type of the mapped values.

    Parameters

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

      A function that maps each value of the observer.

        • (value): T

        • Parameters

          Returns T

    Returns TObserver<T>

    • An observer with the mapped values.

mapAsync

  • mapAsync<T>(callbackfn, fallbackfn?): TObserver<T>

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

    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.

        • (value): Promise<T>

        • Parameters

          Returns Promise<T>

    • Optionalfallbackfn: ((e: Error) => void)

      The optional fallback function that handles errors during mapping.

        • (e): void

        • Parameters

          • e: Error

          Returns void

    Returns TObserver<T>

    • Returns a new observer that emits the mapped values.

merge

  • merge<T>(observer): TObserver<Data | T>

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

    Type Parameters

    • T = any

    Parameters

    • observer: TObserver<T>

      The observer to merge with the current observer.

    Returns TObserver<Data | T>

    • A new observer that emits values from both observers.

next

  • next(data): Promise<void>

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

    Parameters

    • data: Data

      The data to be set.

    Returns Promise<void>

    Resolves when super class's next method is called.

once

  • once(callback): (() => void)

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

    Parameters

    • callback: Function

      The function to be executed only once.

    Returns (() => void)

    • A function that removes the registered event listener.
      • (): void

      • Returns void

reduce

  • reduce<T>(callbackfn, begin): TObserver<T>

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

    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

        • (acm, cur): T

        • Parameters

          Returns T

    • 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?): TObserver<Data>

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

    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 InnerArr[]
                                ? InnerArr extends readonly (...)[]
                                    ? (...) extends (...)
                                        ? (...)
                                        : (...)
                                    : InnerArr
                                : InnerArr
                            : InnerArr
                        : InnerArr
                    : InnerArr
                : InnerArr
            : InnerArr
        : Data)[]>

  • Splits the observed data into batches of arrays.

    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 InnerArr[]
                                ? InnerArr extends readonly (...)[]
                                    ? (...) extends (...)
                                        ? (...)
                                        : (...)
                                    : InnerArr
                                : InnerArr
                            : InnerArr
                        : InnerArr
                    : InnerArr
                : InnerArr
            : InnerArr
        : Data)[]>

    • The observer that emits batches of arrays.

subscribe

  • subscribe(callback): (() => void)

  • Subscribes to an event.

    Parameters

    • callback: Function

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

    Returns (() => void)

    • A function to unsubscribe from the event.
      • (): void

      • Returns void

tap

  • tap(callbackfn): TObserver<Data>

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

    Parameters

    • callbackfn: ((value: Data) => void)
        • (value): void

        • Parameters

          Returns void

    Returns TObserver<Data>

toIteratorContext

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

  • Converts the current object to an iterator context.

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

    The iterator context representing the current object.

    • done:function
      • done(): void

      • Returns void

    • iterate:function
      • iterate(): AsyncGenerator<Data, void, unknown>

      • Returns AsyncGenerator<Data, void, unknown>

    Function

toObserver

  • toObserver(): TObserver<Data>

  • Creates a new observer.

    Returns TObserver<Data>

    The observer instance.

toPromise

  • toPromise(): Promise<Data>

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

    Returns Promise<Data>

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

    Function

    toPromise

    Instance

unsubscribeAll

  • unsubscribeAll(): void

  • Unsubscribes all event listeners.

    Returns void

    • No return value.

    Function

    unsubscribeAll

    Instance

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