Subscription

class stable

Represents a disposable resource, such as the execution of an Observable. A Subscription has one important method, unsubscribe, that takes no argument and just disposes the resource held by the subscription.

class Subscription implements SubscriptionLike { static EMPTY: Subscription constructor(unsubscribe?: () => void) closed: [object Object] unsubscribe(): void add(teardown: TeardownLogic): Subscription remove(subscription: Subscription): void }

Subclasses

Subscriber

Description

Additionally, subscriptions may be grouped together through the add() method, which will attach a child Subscription to the current Subscription. When a Subscription is unsubscribed, all its children (and its grandchildren) will be unsubscribed as well.

Static Properties

Property	Type	Description
EMPTY	`Subscription`

Constructor

constructor(unsubscribe?: () => void)

Parameters

unsubscribe

Optional. Default is undefined.

A function describing how to perform the disposal of resources when the unsubscribe method is called.

Properties

Property	Type	Description
closed	`[object Object]`	A flag to indicate whether this Subscription has already been unsubscribed.

Methods

unsubscribe()
Disposes the resources held by the subscription. May, for instance, cancel an ongoing Observable execution or cancel any other type of work that started when the Subscription was created.
unsubscribe(): void Parameters There are no parameters. Returns `void`:

unsubscribe()

Disposes the resources held by the subscription. May, for instance, cancel an ongoing Observable execution or cancel any other type of work that started when the Subscription was created.

unsubscribe(): void

Parameters

There are no parameters.

Returns

void:

add()

Adds a tear down to be called during the unsubscribe() of this Subscription. Can also be used to add a child subscription.

add(teardown: TeardownLogic): Subscription

Parameters

teardown

The additional logic to execute on teardown.

Returns

Subscription: Returns the Subscription used or created to be added to the inner subscriptions list. This Subscription can be used with remove() to remove the passed teardown logic from the inner subscriptions list.

If the tear down being added is a subscription that is already unsubscribed, is the same reference add is being called on, or is Subscription.EMPTY, it will not be added.

If this subscription is already in an closed state, the passed tear down logic will be executed immediately.

When a parent subscription is unsubscribed, any child subscriptions that were added to it are also unsubscribed.

remove()

Removes a Subscription from the internal list of subscriptions that will unsubscribe during the unsubscribe process of this Subscription.

remove(subscription: Subscription): void

Parameters

subscription

The subscription to remove.

Returns

void: