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off() function

Detaches a callback previously attached with on().

Detach a callback previously attached with on(). Note that if on() was called multiple times with the same eventType and callback, the callback will be called multiple times for each event, and off() must be called multiple times to remove the callback. Calling off() on a parent listener will not automatically remove listeners registered on child nodes, off() must also be called on any child listeners to remove the callback.

If a callback is not specified, all callbacks for the specified eventType will be removed. Similarly, if no eventType is specified, all callbacks for the Reference will be removed.

Individual listeners can also be removed by invoking their unsubscribe callbacks.

Signature:

export declare function off(query: Query, eventType?: EventType, callback?: (snapshot: DataSnapshot, previousChildName?: string | null) => unknown): void;

Parameters

Parameter	Type	Description
query	Query	The query that the listener was registered with.
eventType	EventType	One of the following strings: "value", "child_added", "child_changed", "child_removed", or "child_moved." If omitted, all callbacks for the Reference will be removed.
callback	(snapshot: DataSnapshot, previousChildName?: string | null) => unknown	The callback function that was passed to on() or undefined to remove all callbacks.

Returns:

void