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    Class DocumentSnapshot (4.15.1)

    A DocumentSnapshot is an immutable representation for a document in a Firestore database. The data can be extracted with [data()] or [get(fieldPath)] to get a specific field.

    For a DocumentSnapshot that points to a non-existing document, any data access will return 'undefined'. You can use the [exists] property to explicitly verify a document's existence.

    DocumentSnapshot

    Package

    @google-cloud/firestore

    Constructors

    (constructor)(ref, _fieldsProto, readTime, createTime, updateTime)

      constructor 
 ( 
 ref 
 : 
  
 DocumentReference<T> 
 , 
  
 _fieldsProto 
 ?: 
  
 ApiMapValue 
  
 | 
  
 undefined 
 , 
  
 readTime 
 ?: 
  
 Timestamp 
 , 
  
 createTime 
 ?: 
  
 Timestamp 
 , 
  
 updateTime 
 ?: 
  
 Timestamp 
 );

    Constructs a new instance of the DocumentSnapshot class

    Parameters
    Name Description
    ref DocumentReference <T>

    The reference to the document.
    _fieldsProto ApiMapValue | undefined

    The fields of the Firestore Document Protobuf backing this document (or undefined if the document does not exist).
    readTime Timestamp

    The time when this snapshot was read (or undefined if the document exists only locally).
    createTime Timestamp

    The time when the document was created (or undefined if the document does not exist).
    updateTime Timestamp

    The time when the document was last updated (or undefined if the document does not exist).

    Properties

    _fieldsProto

      readonly 
  
 _fieldsProto 
 ?: 
  
 ApiMapValue 
  
 | 
  
 undefined 
 ;
    Property Value
    Type Description
    ApiMapValue | undefined

    createTime

      get 
  
 createTime 
 () 
 : 
  
 Timestamp 
  
 | 
  
 undefined 
 ;

    The time the document was created. Undefined for documents that don't exist.

    {Timestamp|undefined} DocumentSnapshot#createTime

    Property Value
    Type Description
    Timestamp | undefined
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then(documentSnapshot => { if (documentSnapshot.exists) { let createTime = documentSnapshot.createTime; console.log( Document created at '${createTime.toDate()}' ); } });

    exists

      get 
  
 exists 
 () 
 : 
  
 boolean 
 ;

    True if the document exists.

    {boolean} DocumentSnapshot#exists

    Property Value
    Type Description
    boolean
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then((documentSnapshot) => { if (documentSnapshot.exists) { console.log( Data: ${JSON.stringify(documentSnapshot.data())} ); } });

    id

      get 
  
 id 
 () 
 : 
  
 string 
 ;

    The ID of the document for which this DocumentSnapshot contains data.

    {string} DocumentSnapshot#id

    Property Value
    Type Description
    string
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then((documentSnapshot) => { if (documentSnapshot.exists) { console.log( Document found with name '${documentSnapshot.id}' ); } });

    readTime

      get 
  
 readTime 
 () 
 : 
  
 Timestamp 
 ;

    The time this snapshot was read.

    {Timestamp} DocumentSnapshot#readTime

    Property Value
    Type Description
    Timestamp
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then(documentSnapshot => { let readTime = documentSnapshot.readTime; console.log( Document read at '${readTime.toDate()}' ); });

    ref

      get 
  
 ref 
 () 
 : 
  
 DocumentReference<T> 
 ;

    A [DocumentReference] DocumentReference for the document stored in this snapshot.

    {DocumentReference} DocumentSnapshot#ref

    Property Value
    Type Description
    DocumentReference <T>
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then((documentSnapshot) => { if (documentSnapshot.exists) { console.log( Found document at '${documentSnapshot.ref.path}' ); } });

    updateTime

      get 
  
 updateTime 
 () 
 : 
  
 Timestamp 
  
 | 
  
 undefined 
 ;

    The time the document was last updated (at the time the snapshot was generated). Undefined for documents that don't exist.

    {Timestamp|undefined} DocumentSnapshot#updateTime

    Property Value
    Type Description
    Timestamp | undefined
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then(documentSnapshot => { if (documentSnapshot.exists) { let updateTime = documentSnapshot.updateTime; console.log( Document updated at '${updateTime.toDate()}' ); } });

    Methods

    data()

      data 
 () 
 : 
  
 T 
  
 | 
  
 undefined 
 ;

    Retrieves all fields in the document as an object. Returns 'undefined' if the document doesn't exist.

    Returns
    Type Description
    T | undefined

    {T|undefined} An object containing all fields in the document or 'undefined' if the document doesn't exist.
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.get().then(documentSnapshot => { let data = documentSnapshot.data(); console.log( Retrieved data: ${JSON.stringify(data)} ); });

    get(field)

      get 
 ( 
 field 
 : 
  
 string 
  
 | 
  
 FieldPath 
 ) 
 : 
  
 any 
 ;

    Retrieves the field specified by field .

    Parameter
    Name Description
    field string | FieldPath

    The field path (e.g. 'foo' or 'foo.bar') to a specific field.
    Returns
    Type Description
    any

    {*} The data at the specified field location or undefined if no such field exists.
    Example

    let documentRef = firestore.doc('col/doc');

    documentRef.set({ a: { b: 'c' }}).then(() => { return documentRef.get(); }).then(documentSnapshot => { let field = documentSnapshot.get('a.b'); console.log( Retrieved field value: ${field} ); });

    isEqual(other)

      isEqual 
 ( 
 other 
 : 
  
 firestore 
 . 
 DocumentSnapshot<T> 
 ) 
 : 
  
 boolean 
 ;

    Returns true if the document's data and path in this DocumentSnapshot is equal to the provided value.

    Parameter
    Name Description
    other FirebaseFirestore.DocumentSnapshot <T>

    The value to compare against. {boolean} true if this DocumentSnapshot is equal to the provided value.
    Returns
    Type Description
    boolean
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