Sentinel values that can be used when writing documents with set(), create() or update().
FieldValue
Package
@google-cloud/firestoreConstructors
(constructor)()
constructor
();
Constructs a new instance of the FieldValue
class
Methods
arrayRemove(elements)
static
arrayRemove
(...
elements
:
unknown
[])
:
FieldValue
;
Returns a special value that can be used with set(), create() or update() that tells the server to remove the given elements from any array value that already exists on the server. All instances of each element specified will be removed from the array. If the field being modified is not already an array it will be overwritten with an empty array.
elements
unknown[]
The elements to remove from the array. {FieldValue} The FieldValue sentinel for use in a call to set(), create() or update().
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
documentRef
.
update
(
'array'
,
Firestore
.
FieldValue
.
arrayRemove
(
'foo'
)
).
then
(()
=
>
{
return
documentRef
.
get
();
}).
then
(
doc
=
>
{
// doc.get('array') no longer contains field 'foo'
});
arrayUnion(elements)
static
arrayUnion
(...
elements
:
unknown
[])
:
FieldValue
;
Returns a special value that can be used with set(), create() or update() that tells the server to union the given elements with any array value that already exists on the server. Each specified element that doesn't already exist in the array will be added to the end. If the field being modified is not already an array it will be overwritten with an array containing exactly the specified elements.
elements
unknown[]
The elements to union into the array. {FieldValue} The FieldValue sentinel for use in a call to set(), create() or update().
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
documentRef
.
update
(
'array'
,
Firestore
.
FieldValue
.
arrayUnion
(
'foo'
)
).
then
(()
=
>
{
return
documentRef
.
get
();
}).
then
(
doc
=
>
{
// doc.get('array') contains field 'foo'
});
delete()
static
delete
()
:
FieldValue
;
Returns a sentinel for use with update() or set() with {merge:true} to mark a field for deletion.
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
let
data
=
{
a
:
'b'
,
c
:
'd'
};
documentRef
.
set
(
data
).
then
(()
=
>
{
return
documentRef
.
update
({
a
:
Firestore
.
FieldValue
.
delete
()});
}).
then
(()
=
>
{
// Document now only contains { c: 'd' }
});
increment(n)
static
increment
(
n
:
number
)
:
FieldValue
;
Returns a special value that can be used with set(), create() or update() that tells the server to increment the the field's current value by the given value.
If either current field value or the operand uses floating point precision, both values will be interpreted as floating point numbers and all arithmetic will follow IEEE 754 semantics. Otherwise, integer precision is kept and the result is capped between -2^63 and 2^63-1.
If the current field value is not of type 'number', or if the field does not yet exist, the transformation will set the field to the given value.
n
number
The value to increment by. {FieldValue} The FieldValue sentinel for use in a call to set(), create() or update().
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
documentRef
.
update
(
'counter'
,
Firestore
.
FieldValue
.
increment
(
1
)
).
then
(()
=
>
{
return
documentRef
.
get
();
}).
then
(
doc
=
>
{
// doc.get('counter') was incremented
});
isEqual(other)
isEqual
(
other
:
firestore
.
FieldValue
)
:
boolean
;
Returns true if this FieldValue
is equal to the provided value.
other
firestore.FieldValue
The value to compare against. {boolean} true if this FieldValue
is equal to the provided value.
boolean
let
fieldValues
=
[
Firestore
.
FieldValue
.
increment
(
-
1.0
),
Firestore
.
FieldValue
.
increment
(
-
1
),
Firestore
.
FieldValue
.
increment
(
-
0.0
),
Firestore
.
FieldValue
.
increment
(
-
0
),
Firestore
.
FieldValue
.
increment
(
0
),
Firestore
.
FieldValue
.
increment
(
0.0
),
Firestore
.
FieldValue
.
increment
(
1
),
Firestore
.
FieldValue
.
increment
(
1.0
)
];
let
equal
=
0
;
for
(
let
i
=
0
;
i
<
fieldvalues
.
length
;
=
""
++
i
)
=
""
{
=
""
for
=
""
(
let
=
""
j
=
"i"
+=
""
1
;
=
""
j
=
""
><
fieldvalues
.
length
;
=
""
++
j
)
=
""
{
=
""
if
=
""
(
fieldvalues
[
i
].
isequal
(
fieldvalues
[
j
]))
=
""
{
=
""
++
equal
;
=
""
}
=
""
}
=
""
}
=
""
console
.
log
(
`found=""
${
equal
}
="" equalities.`
);
=
""
>
serverTimestamp()
static
serverTimestamp
()
:
FieldValue
;
Returns a sentinel used with set(), create() or update() to include a server-generated timestamp in the written data.
{FieldValue} The FieldValue sentinel for use in a call to set(), create() or update().
let
documentRef
=
firestore
.
doc
(
'col/doc'
);
documentRef
.
set
({
time
:
Firestore
.
FieldValue
.
serverTimestamp
()
}).
then
(()
=
>
{
return
documentRef
.
get
();
}).
then
(
doc
=
>
{
console
.
log
(
`Server time set to
${
doc
.
get
(
'time'
)
}
`
);
});
vector(values)
static
vector
(
values
?:
number
[])
:
VectorValue
;
Creates a new VectorValue
constructed with a copy of the given array of numbers.
values
number[]
Create a VectorValue
instance with a copy of this array of numbers.
A new VectorValue
constructed with a copy of the given array of numbers.
