TFieldDataLink

type TFieldDataLink = class(TDataLink)

protected

  procedure ActiveChanged; override;

ActiveChanged - method to process changes in the Active property

  procedure DataSetChanged; override;

DataSetChanged - method to process a change in the DataSet

  procedure EditingChanged; override;

EditingChanged - method for processing changes in the Editing property

  procedure LayoutChanged; override;

LayoutChanged- called if layout is changed: tests validity of field then calls OnLayoutChange event handler

  procedure RecordChanged(); override;

RecordChanged - triggered if the contents of the current record change; calls Reset

  procedure UpdateData; override;

UpdateData - if there are any pending changes, calls OnUpdateData event handler

  procedure FocusControl(); override;

FocusControl - gives this control the input focus; calls the OnFocusRequest event handler

public

  constructor Create;

Create - calls inherited Create then initialises field information

  destructor Destroy; override;

  function Edit;

Edit - if the field can be modified, performs inherited Edit and shows editing status

  procedure Modified;

Modified sets the IsModified local variable to True

  procedure Reset;

Reset - checks that link is active, calls the OnDataChange event handler then sets IsModified to False

  property Control: TComponent; [rw]

The Control to which this datalink is attached

  property Field: TField; [r]

The Field to which the datalink is attached

  property FieldName: String; [rw]

FieldName - the name of the attached field, stored as a string

  property CanModify: Boolean; [r]

CanModify - True if the linked field is capable of being modified

  property Editing: Boolean; [r]

Editing - True if the linked field is being edited

  property OnDataChange: TNotifyEvent; [rw]

OnDataChange - event handler for a change in the data

  property OnEditingChange: TNotifyEvent; [rw]

OnEditingChange - event handler for a changed in the Editing property

  property OnUpdateData: TNotifyEvent; [rw]

OnUpdateData - event handler for updating any pending changes in the data

  property OnActiveChange: TNotifyEvent; [rw]

OnActiveChange - event handler for a change in the Active property

  property OnFocusRequest: TNotifyEvent; [rw]

OnFocusRequest - event handler for a request to give focus

  property OnLayoutChange: TNotifyevent; [rw]

OnLayoutChange - event handler for a change in the layout

end;

TFieldDataLink

TFieldDataLink - forms a link between a database field and an action

TDataLink

TPersistent

TObject