TFieldDataLink

type TFieldDataLink = class(TDataLink)

protected

  procedure ActiveChanged; override;

ActiveChanged - method to process changes in the Active property.

  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;

Signals the OnUpdateData event handler for pending changes to the linked dataset.

  procedure FocusControl(); override;

FocusControl gives the input focus to the data-aware control in the class instance.

public

  constructor Create;

Constructor for the class instance.

  function Edit;

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

  procedure Modified;

Updates the class when the linked dataset enters an edit state.

  procedure Reset;

Checks whether the 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]

True if the linked field is capable of being modified.

  property Editing: Boolean; [r]

True if the linked field is being edited.

  property EditingSource: Boolean; [r]

Indicates if the data link is changing its source properties.

  property OnDataChange: TNotifyEvent; [rw]

Event handler signalled when the field data link has been changed.

  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.

end;

TFieldDataLink

Maintains an association between a control, an action, and a field in a linked dataset.

TDataLink

TPersistent,IFPObserved

TObject

TDBLookup

TDBLookup - used as source of data by TDBLookupListBox or TDBLookupComboBox, to find data from a lookup table.

TDBEdit

TDBEdit - a data-aware edit box for processing a single text-string from a dataset.

TDBText

Displays a string value stored in a dataset field.

TDBRadioGroup

TDBRadioGroup is a data-aware version of TRadioGroup, providing a series of mutually exclusive buttons to select an entry to insert into a database field.

TDBCheckBox

Implements a data-aware check box control.

TDBMemo

TDBMemo is a data-aware Memo box to process the multi-line text of a single field in a dataset.

TDBGroupBox

TDBGroupBox is a data-aware version of TGroupBox, allowing a number of data-aware objects to be grouped together on a form.

TDBImage

TDBImage - a data-aware Image box to display a single image from a dataset.

TDBCalendar

TDBCalendar - a data-aware version of TCalendar, for selecting a date to store in a database field.

TCustomDBComboBox

TCustomDBComboBox is a data-aware combo-box for displaying information from a database.

TDataLink