DocumentChange interface

A DocumentChange represents a change to the documents matching a query. It contains the document affected and the type of change that occurred.

Signature:

export declare interface DocumentChange<AppModelType = DocumentData, DbModelType extends DocumentData = DocumentData> 

Properties

Property Type Description
doc QueryDocumentSnapshot<AppModelType, DbModelType> The document affected by this change.
newIndex number The index of the changed document in the result set immediately after this DocumentChange (i.e. supposing that all prior DocumentChange objects and the current DocumentChange object have been applied). Is -1 for 'removed' events.
oldIndex number The index of the changed document in the result set immediately prior to this DocumentChange (i.e. supposing that all prior DocumentChange objects have been applied). Is -1 for 'added' events.
type DocumentChangeType The type of change ('added', 'modified', or 'removed').

DocumentChange.doc

The document affected by this change.

Signature:

readonly doc: QueryDocumentSnapshot<AppModelType, DbModelType>;

DocumentChange.newIndex

The index of the changed document in the result set immediately after this DocumentChange (i.e. supposing that all prior DocumentChange objects and the current DocumentChange object have been applied). Is -1 for 'removed' events.

Signature:

readonly newIndex: number;

DocumentChange.oldIndex

The index of the changed document in the result set immediately prior to this DocumentChange (i.e. supposing that all prior DocumentChange objects have been applied). Is -1 for 'added' events.

Signature:

readonly oldIndex: number;

DocumentChange.type

The type of change ('added', 'modified', or 'removed').

Signature:

readonly type: DocumentChangeType;