Written reference online DBDateTime controls, as data-aware controls associated time type, use this control to run the program, for the first time with the method of input in the control input date, when the input is invalid, such as the control the date of the associated data in the database is the 1990-01-01, to run the program, click on the control, in 1988 where input, on click to jump to controls that it shows the recovery from 1988 to 1990, input, there is no problem for a second time,


The control code:

The unit DBDateTime;

Interface

USES the
SysUtils, Classes, Controls, ComCtrls DBCtrls, DB, Windows, Messages, Dialogs.

Type
TDBDateTime=class (TDateTimePicker)
Private
FDataLink: TFieldDataLink;
FAlignment: TAlignment;
Procedure SetAlignment (const Value: TAlignment);
Procedure DataChange (Sender: TObject);
Procedure EditingChange (Sender: TObject);
Procedure the UpdateData (Sender: TObject);
The function GetDataField: WideString;
The function GetDataSource: TDataSource;
Procedure SetDataField (const Value: WideString);
Procedure SetDataSource (const Value: TDataSource);
Procedure CMExit (var Message: TCMExit); The message CM_EXIT;
{Private declarations}
Protected
Procedure Change; Override.
Procedure Notification (AComponent: TComponent;
Operation: TOperation); Override.
{Protected declarations}
Public
The constructor Create (AOwner: TComponent); Override.
The destructor Destroy; Override.
{Public declarations}
Published
The property Alignment: TAlignment read FAlignment write SetAlignment;
The property DataField: WideString read GetDataField write SetDataField;
The property DataSource: TDataSource read GetDataSource write SetDataSource;
end;

Procedure Register;

Implementation

Procedure Register;
The begin
RegisterComponents (' Data Controls', [TDBDateTime]);
end;

{TDBDateTime}

Procedure TDBDateTime. Change;
The begin
FDataLink. Modified;
If not FDataLink. Editing then
FdataLink. Edit;
//postmessage (Self. Handle, wm_keydown, VK_RIGHT, 0).
Inherited Change;
end;

Procedure TDBDateTime. CMExit (var Message: TCMExit);
The begin
Try
FDataLink. UpdateRecord;
Except,
//SelectAll;
SetFocus;
Raise;
end;

DoExit;
end;

The constructor TDBDateTime. Create (AOwner: TComponent);
The begin
Inherited the Create (Aowner);
FDataLink:=TFieldDataLink. Create;
FDataLink. Control:=the Self;
FDataLink. OnDataChange:=DataChange;
FDataLink. OnEditingChange:=EditingChange;
FDataLink. OnUpdateData:=the UpdateData;
end;

Procedure TDBDateTime. DataChange (Sender: TObject);
The begin
If FDataLink. Field & lt;> Nil then
The begin
If FDatalink. Field. AsDateTime=0 then DateTime:=1
The else DateTime:=FDatalink Field. AsDateTime;
End the else
The begin
DateTime: now=();
end;

end;

Destructor TDBDateTime. Destroy;
The begin
FDataLink. OnDataChange:=nil;
FDataLink. OnUpdateData:=nil;
FDataLink. Free;
FDataLink:=nil;

Inherited Destroy;
end;

Procedure TDBDateTime. EditingChange (Sender: TObject);
The begin
If (a DataSource & lt;> Nil) and (DataField & lt;> ") then
FDataLink. Edit;
end;

The function TDBDateTime. GetDataField: WideString;
The begin
Result:=FDataLink. FieldName;
end;

The function TDBDateTime. GetDataSource: TDataSource;
The begin
Result:=FDataLink. The DataSource;
end;

Procedure TDBDateTime. Notification (AComponent: TComponent;
Operation: TOperation);
The begin
Inherited Notification (AComponent, Operation);
If (Operation=opRemove) and (FDataLink & lt;> Nil) and
(AComponent=DataSource) then the DataSource:=nil;
end;

Procedure TDBDateTime. SetAlignment (const Value: TAlignment);
Var
Style: DWORD;
The begin
If FAlignment & lt;> The Value then
The begin
FAlignment:=Value;
Style:=GetWindowLong (Handle, GWL_STYLE);
Style:=style and (not ES_LEFT) and (not ES_CENTER) and (not ES_RIGHT);
Case FAlignment of
TaLeftJustify: SetWindowLong (Handle, GWL_STYLE, style or ES_LEFT);
TaRightJustify: SetWindowLong (Handle, GWL_STYLE, style or ES_RIGHT);
TaCenter: SetWindowLong (Handle, GWL_STYLE, style or ES_CENTER);
end;
Invalidate.
end;
end;

Procedure TDBDateTime. SetDataField (const Value: WideString);
The begin
FDataLink. FieldName:=Value;
end;

Procedure TDBDateTime. SetDataSource (const Value: TDataSource);
The begin
If not (FDataLink DataSourceFixed and (csLoading ComponentState) in) then
FDataLink. The DataSource:=Value;
If the Value & lt;> Nil Value. Then FreeNotification (Self);
end;

Procedure TDBDateTime. The UpdateData (Sender: TObject);
The begin
//ShowMessage (DateTimeToStr (DateTime));
FDatalink. Field. AsDateTime:=DateTime;
end;

end.

CodePudding user response:

Using InfoPower date of control,,,