FirebaseFirestore Framework Reference

FIRFieldValue

@interface FIRFieldValue : NSObject

Sentinel values that can be used when writing document fields with setData() or updateData().

• +fieldValueForDelete

  Used with updateData() to mark a field for deletion.

  Declaration

  Objective-C

  + (nonnull instancetype)fieldValueForDelete;

• +fieldValueForServerTimestamp

  Used with setData() or updateData() to include a server-generated timestamp in the written data.

  Declaration

  Objective-C

  + (nonnull instancetype)fieldValueForServerTimestamp;

• +fieldValueForArrayUnion:

  Returns a special value that can be used with setData() or updateData() 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.

  Declaration

  Objective-C

  + (nonnull instancetype)fieldValueForArrayUnion:(nonnull NSArray<id> *)elements;

  Parameters

  elements

  The elements to union into the array.

  Return Value

  The FieldValue sentinel for use in a call to setData() or updateData().

• +fieldValueForArrayRemove:

  Returns a special value that can be used with setData() or updateData() 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.

  Declaration

  Objective-C

  + (nonnull instancetype)fieldValueForArrayRemove:
      (nonnull NSArray<id> *)elements;

  Parameters

  elements

  The elements to remove from the array.

  Return Value

  The FieldValue sentinel for use in a call to setData() or updateData().

• +fieldValueForDoubleIncrement:

  Returns a special value that can be used with setData() or updateData() that tells the server to increment the field’s current value by the given value.

  If the current value is an integer or a double, both the current and the given value will be interpreted as doubles and all arithmetic will follow IEEE 754 semantics. Otherwise, the transformation will set the field to the given value.

  Declaration

  Objective-C

  + (nonnull instancetype)fieldValueForDoubleIncrement:(double)d;

  Parameters

  d	The double value to increment by.

  Return Value

  The FieldValue sentinel for use in a call to setData() or updateData().

• +fieldValueForIntegerIncrement:

  Returns a special value that can be used with setData() or updateData() that tells the server to increment the field’s current value by the given value.

  If the current field value is an integer, possible integer overflows are resolved to LONG_MAX or LONG_MIN. If the current field value is a double, both values will be interpreted as doubles and the arithmetic will follow IEEE 754 semantics.

  If field is not an integer or double, or if the field does not yet exist, the transformation will set the field to the given value.

  Declaration

  Objective-C

  + (nonnull instancetype)fieldValueForIntegerIncrement:(int64_t)l;

  Parameters

  l	The integer value to increment by.

  Return Value

  The FieldValue sentinel for use in a call to setData() or updateData().

• +vectorWithArray:

  Creates a new VectorValue constructed with a copy of the given array of NSNumbers.

  Declaration

  Objective-C

  + (nonnull FIRVectorValue *)vectorWithArray:
      (nonnull NSArray<NSNumber *> *)array;

  Parameters

  array

  Create a VectorValue instance with a copy of this array of NSNumbers.

  Return Value

  A new VectorValue constructed with a copy of the given array of NSNumbers.