A konzolhoz

FirebaseFirestore Framework Reference

FieldValue

class FieldValue : NSObject

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

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

    Declaration

    Swift

    class func delete() -> Self
  • Used with setData() or updateData() to include a server-generated timestamp in the written data.

    Declaration

    Swift

    class func serverTimestamp() -> Self
  • 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

    Swift

    class func arrayUnion(_ elements: [Any]) -> Self

    Parameters

    elements

    The elements to union into the array.

    Return Value

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

  • 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

    Swift

    class func arrayRemove(_ elements: [Any]) -> Self

    Parameters

    elements

    The elements to remove from the array.

    Return Value

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

  • 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

    Swift

    class func increment(_ d: Double) -> Self

    Parameters

    d

    The double value to increment by.

    Return Value

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

  • 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

    Swift

    class func increment(_ l: Int64) -> Self

    Parameters

    l

    The integer value to increment by.

    Return Value

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