[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'DB' (#fcl)

TDataSet.IsUniDirectional

Is the dataset unidirectional (i.e. forward scrolling only)

Declaration

Source position: db.pas line 1734

public property TDataSet.IsUniDirectional : Boolean
  read FIsUniDirectional
  default False;

Description

IsUniDirectional is True if the dataset is unidirectional. By default it is False, i.e. scrolling backwards is allowed. If the dataset is unidirectional, then any attempt to scroll backwards (using one of TDataset.Prior or TDataset.Last), random positioning of the cursor, editing or filtering will result in an EDatabaseError. Unidirectional datasets are also not suitable for display in a grid, as they have only 1 record in memory at any given time: they are only useful for performing an action on all records:

With MyDataset do
  While not EOF do
    begin
    DoSomething;
    Next;
    end;

See also

TDataset.Prior

  

Go to the previous record

TDataset.Next

  

Go to the next record in the dataset.


Documentation generated on: May 14 2021