new QueryDocumentSnapshot()
A QueryDocumentSnapshot contains data read from a document in your Firestore database as part of a query. The document is guaranteed to exist and its data can be extracted with data() or get() to get a specific field.
A QueryDocumentSnapshot offers the same API surface as a DocumentSnapshot. Since query results contain only existing documents, the exists property will always be true and data() will never return 'undefined'.
Extends
Members
createTime
The time the document was created.
- Overrides:
Example
```
let query = firestore.collection('col');
query.get().forEach(snapshot => {
console.log(`Document created at '${snapshot.createTime.toDate()}'`);
});
```
exists
True if the document exists.
- Inherited From:
Example
```
let documentRef = firestore.doc('col/doc');
documentRef.get().then((documentSnapshot) => {
if (documentSnapshot.exists) {
console.log(`Data: ${JSON.stringify(documentSnapshot.data())}`);
}
});
```
id
The ID of the document for which this DocumentSnapshot contains data.
- Inherited From:
Example
```
let documentRef = firestore.doc('col/doc');
documentRef.get().then((documentSnapshot) => {
if (documentSnapshot.exists) {
console.log(`Document found with name '${documentSnapshot.id}'`);
}
});
```
readTime
The time this snapshot was read.
- Inherited From:
Example
```
let documentRef = firestore.doc('col/doc');
documentRef.get().then(documentSnapshot => {
let readTime = documentSnapshot.readTime;
console.log(`Document read at '${readTime.toDate()}'`);
});
```
ref
A DocumentReference for the document stored in this snapshot.
- Inherited From:
Example
```
let documentRef = firestore.doc('col/doc');
documentRef.get().then((documentSnapshot) => {
if (documentSnapshot.exists) {
console.log(`Found document at '${documentSnapshot.ref.path}'`);
}
});
```
updateTime
The time the document was last updated (at the time the snapshot was generated).
- Overrides:
Example
```
let query = firestore.collection('col');
query.get().forEach(snapshot => {
console.log(`Document updated at '${snapshot.updateTime.toDate()}'`);
});
```
Methods
data() → {T}
Retrieves all fields in the document as an object.
Returns:
Type | Description |
---|---|
T |
An object containing all fields in the document. |
- Overrides:
Example
```
let query = firestore.collection('col');
query.get().forEach(documentSnapshot => {
let data = documentSnapshot.data();
console.log(`Retrieved data: ${JSON.stringify(data)}`);
});
```
get(field) → {*}
Retrieves the field specified by field
.
Parameters:
Name | Type | Description |
---|---|---|
field |
string | FieldPath |
The field path (e.g. 'foo' or 'foo.bar') to a specific field. |
Returns:
Type | Description |
---|---|
* |
The data at the specified field location or undefined if no such field exists. |
- Inherited From:
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) → {boolean}
Returns true if the document's data and path in this DocumentSnapshot
is
equal to the provided value.
Parameters:
Name | Type | Description |
---|---|---|
other |
* |
The value to compare against. |
Returns:
Type | Description |
---|---|
boolean |
true if this |
- Inherited From: