Валентин Озеров - Советы по Delphi. Версия 1.4.3 от 1.1.2001
// BDEDataSync =
// function(const DBHandle: HDBIDB; const DSHandle: HDBICur): Boolean;
// stdcall;
// {Организация перехвата ошибок загрузки DLL}
// EDLLLoadError = class(Exception);
// var h: hwnd;
// p: BDEDataSync;
// LastError: DWord;
// begin
// UpdateCursorPos;
// Try
// h := loadLibrary('EDITDLL.DLL');
// {Примечание для пользователей Delphi 1.0: Поскольку Win32
// LoadLibrary при неудачной загрузке DLL возвращает NULL,
// поэтому для поиска ошибки необходим вызов GetLastError,
// Win16 LoadLibrary возвращает значение ошибки (меньше чем
// HINSTANCE_ERROR), которая для выяснения причин неудачной
// загрузки может затем провериться с помощью Win16API SDK.}
// if h = 0 then begin
// LastError := GetLastError;
// Raise EDLLLoadError.create(IntToStr(LastError) +
// ': Невозможно загрузить DLL');
// end;
// try
// p := getProcAddress(h, 'EditData');
// if p(DBHandle, Handle) then Resync([]);
// finally
// freeLibrary(h);
// end;
// Except
// On E: EDLLLoadError do
// MessageDLG(E.Message, mtInformation, [mbOk],0);
// end;
// end;
// {или}
function EditData(const DBHandle: HDBIDB; const DSHandle: HDBICur): Boolean; stdcall external 'EDITDLL.DLL' name 'EditData';
procedure TDBMainForm.EditButtonClick(Sender: TObject);
begin
with Table1 do begin
UpdateCursorPos;// Вызываем процедуру EditData из EditDll.dll.
if EditData(DBHandle, Handle) then Resync([]);
end;
end;
procedure TDBMainForm.DBGrid1DblClick(Sender: TObject);
begin
EditButton.Click;
end;
end.
Проект EDIT DLL
{ EDITDLL.DPR }
library editdll;
uses SysUtils, Classes, editform in 'editform.pas' {DBEditForm};
exports EditData;
begin
end.
{ EDITFORM.PAS }
unit editform;
interface
uses SysUtils, Windows, Messages, Classes, Graphics, Controls, StdCtrls, Forms, DBCtrls, DB, DBTables, Mask, ExtCtrls, BDE;
type
TTableClone = class;
TDBEditForm = class(TForm);
ScrollBox: TScrollBox;
Label1: TLabel;
EditName: TDBEdit;
Label2: TLabel;
EditCapital: TDBEdit;
Label3: TLabel;
EditContinent: TDBEdit;
Label4: TLabel;
EditArea: TDBEdit;
Label5: TLabel;
EditPopulation: TDBEdit;
DBNavigator: TDBNavigator;
Panel1: TPanel;
DataSource1: TDataSource;
Panel2: TPanel;
Database1: TDatabase;
OKButton: TButton;
private
TableClone: TTableClone;
end;
{ TTableClone }
TTableClone = class(TTable)
private
SrcHandle: HDBICur;
protected
function CreateHandle: HDBICur; override;
public
procedure OpenClone(ASrcHandle: HDBICur);
end;
function EditData(const DBHandle: HDBIDB; const DSHandle: HDBICur): Boolean; stdcall;
var DBEditForm: TDBEditForm;
implementation
{$R *.DFM}
{ Экспорт }
function EditData(const DBHandle: HDBIDB; const DSHandle: HDBICur): Boolean; stdcall;
var DBEditForm: TDBEditForm;
begin
DBEditForm := TDBEditForm.Create(Application);
with DBEditForm do try
// Устанавливаем дескриптор Database1 на открытую в текущий момент базу данных
Database1.Handle := DBHandle;
TableClone := TTableClone.Create(DBEditForm);
try
TableClone.DatabaseName := 'DB1';
DataSource1.DataSet := TableClone;
TableClone.OpenClone(DSHandle);
Result := (ShowModal = mrOK);
if Result then begin
TableClone.UpdateCursorPos;
DbiSetToCursor(DSHandle, TableClone.Handle);
end;
finally
TableClone.Free;
end;
finally
Free;
end;
end;
{ TTableClone }
procedure TTableClone.OpenClone(ASrcHandle: HDBICur);
begin
SrcHandle := ASrcHandle;
Open;
DbiSetToCursor(Handle, SrcHandle);
Resync([]);
end;
function TTableClone.CreateHandle: HDBICur
begin
Check(DbiCloneCursor(SrcHandle, False, False, Result));
end;
end.
{ EDITFORM.DFM }
object DBEditForm: TDBEditForm
Left = 201
Top = 118
Width = 354
Height = 289
ActiveControl = Panel1
Caption = 'DBEditForm'
Font.Color = clWindow
TextFont.Height = -11
Font.Name = 'MS Sans Serif'
Font.Style = []
Position = poScreenCenter
PixelsPerInch = 96
TextHeight = 13
object Panel1: TPanel
Left = 0
Top = 0
Width = 346
Height = 41
Align = alTop
TabOrder = 0
object DBNavigator: TDBNavigator
Left = 8
Top = 8
Width = 240
Height = 25
DataSource = DataSource1
Ctl3D = FalseParent
Ctl3D = False
TabOrder = 0
end
object OKButton: TButton
Left = 260
Top = 8
Width = 75
Height = 25
Caption = 'OK'
Default = True
ModalResult = 1
TabOrder = 1
end
end
object Panel2: TPanel
Left = 0
Top = 41
Width = 346
Height = 221
Align = alClient
BevelInner = bvLoweredBorder
Width = 4
Caption = 'Panel2'
TabOrder = 1
object ScrollBox: TScrollBox
Left = 6
Top = 6
Width = 334
Height = 209
HorzScrollBar.Margin = 6
HorzScrollBar.Range = 147
VertScrollBar.Margin = 6
VertScrollBar.Range = 198
Align = alClient
AutoScroll = False
BorderStyle = bsNone
TabOrder = 0
object Label1: TLabel
Left = 6
Top = 6
Width = 28
Height = 13
Caption = 'Name'
FocusControl = EditName
end
object Label2: TLabel
Left = 6
Top = 44
Width = 32
Height = 13
Caption = 'Capital'
FocusControl = EditCapital
end
object Label3: TLabel
Left = 6
Top = 82
Width = 45
Height = 13
Caption = 'Continent'
FocusControl = EditContinent
end
object Label4: TLabel
Left = 6
Top = 120
Width = 22
Height = 13
Caption = 'Area'
FocusControl = EditArea
end
object Label5: TLabel
Left = 6
Top = 158
Width = 50
Height = 13
Caption = 'Population'
FocusControl = EditPopulation
end
object EditName: TDBEdit
Left = 6
Top = 21
Width = 135
Height = 21
DataField = 'Name'
DataSource = DataSource1
MaxLength = 0
TabOrder = 0
end
object EditCapital: TDBEdit
Left = 6
Top = 59
Width = 135
Height = 21
DataField = 'Capital'
DataSource = DataSource1
MaxLength = 0
TabOrder = 1
end
object EditContinent: TDBEdit
Left = 6
Top = 97
Width = 135
Height = 21
DataField = 'Continent'
DataSource = DataSource1
MaxLength = 0
TabOrder = 2
end
object EditArea: TDBEdit
Left = 6
Top = 135
Width = 65
Height = 21
