syndbedit.pas

一个mwEdit控件原码,比mwCuuEdit0.92a功能先进.

{-------------------------------------------------------------------------------
The contents of this file are subject to the Mozilla Public License
Version 1.1 (the "License"); you may not use this file except in compliance
with the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL/

Software distributed under the License is distributed on an "AS IS" basis,
WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
the specific language governing rights and limitations under the License.

The Original Code is: SynDBEdit.pas, released 2000-05-05.
The Original Code is based on DBmwEdit.pas by Vladimir Kuznetsov, part of
the mwEdit component suite.
Portions created by Vladimir Kuznetsov are Copyright (C) 1999 Vladimir Kuznetsov.
All Rights Reserved.

Contributors to the SynEdit and mwEdit projects are listed in the
Contributors.txt file.

Alternatively, the contents of this file may be used under the terms of the
GNU General Public License Version 2 or later (the "GPL"), in which case
the provisions of the GPL are applicable instead of those above.
If you wish to allow use of your version of this file only under the terms
of the GPL and not to allow others to use your version of this file
under the MPL, indicate your decision by deleting the provisions above and
replace them with the notice and other provisions required by the GPL.
If you do not delete the provisions above, a recipient may use your version
of this file under either the MPL or the GPL.

$Id: SynDBEdit.pas,v 1.10 2004/02/04 23:42:10 markonjezic Exp $

You may retrieve the latest version of this file at the SynEdit home page,
located at http://SynEdit.SourceForge.net

Known Issues:
-------------------------------------------------------------------------------}

{$IFNDEF QSYNDBEDIT}
unit SynDBEdit;
{$ENDIF}

{$I SynEdit.inc}

interface

uses
{$IFNDEF SYN_COMPILER_3_UP}
  DbTables,
{$ENDIF}
{$IFDEF SYN_CLX}
  Qt,
  QControls,
  QDBCtrls,
  QSynEdit,
  QSynEditKeyCmds,
{$ELSE}
  Windows,
  Messages,
  Controls,
  DbCtrls,
  SynEdit,
  SynEditKeyCmds,
{$ENDIF}
  SysUtils,
  Classes,
  DB;

type
  TCustomDBSynEdit = class(TCustomSynEdit)
  private
    FDataLink: TFieldDataLink;
    fEditing: boolean;
    FOldOnChange : TNotifyEvent;
    FBeginEdit: boolean;
    FLoadData: TNotifyEvent;
    procedure DataChange(Sender: TObject);
    procedure EditingChange(Sender: TObject);
    function GetDataField: string;
    function GetDataSource: TDataSource;
    function GetField: TField;
    procedure SetDataField(const Value: string);
    procedure SetDataSource(Value: TDataSource);
    procedure SetEditing(Value: Boolean);
    procedure UpdateData(Sender: TObject);
  private
    {*****************}
  {$IFNDEF SYN_CLX}
    procedure CMEnter(var Msg: TCMEnter);
      message CM_ENTER;
    procedure CMExit(var Msg: TCMExit);
      message CM_EXIT;
    procedure CMGetDataLink(var Msg: TMessage);
      message CM_GETDATALINK;
  {$ENDIF}
  protected
    function GetReadOnly: boolean; override;
    procedure Loaded; override;
    procedure NewOnChange(Sender: TObject);
    procedure SetReadOnly(Value: boolean); override;
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    procedure DragDrop(Source: TObject; X, Y: Integer); override;
    procedure ExecuteCommand(Command: TSynEditorCommand; AChar: char;
      Data: pointer); override;
    procedure LoadMemo;
    procedure Notification(AComponent: TComponent; Operation: TOperation);
      override;
  {$IFDEF SYN_CLX}
    function EventFilter(Sender: QObjectH; Event: QEventH): Boolean; override;
  {$ENDIF}
  protected
    property DataField: string read GetDataField write SetDataField;
    property DataSource: TDataSource read GetDataSource write SetDataSource;
    property Field: TField read GetField;
    property OnLoadData: TNotifyEvent read fLoadData write fLoadData;
  end;

  TDBSynEdit = class(TCustomDBSynEdit)
  published
    // TCustomDBSynEdit properties
    property DataField;
    property DataSource;
    property Field;
    // TCustomDBSynEdit events
    property OnLoadData;
    // inherited properties
    property Align;
{$IFDEF SYN_COMPILER_4_UP}
    property Anchors;
    property Constraints;
{$ENDIF}
    property Color;
  {$IFNDEF SYN_CLX}
    property Ctl3D;
  {$ENDIF}
    property Enabled;
    property Font;
    property Height;
    property Name;
    property ParentColor;
  {$IFNDEF SYN_CLX}
    property ParentCtl3D;
  {$ENDIF}
    property ParentFont;
    property ParentShowHint;
    property PopupMenu;
    property ShowHint;
    property TabOrder;
    property TabStop default True;
    property Tag;
    property Visible;
    property Width;
    // inherited events
    property OnClick;
    property OnDblClick;
    property OnDragDrop;
    property OnDragOver;
{$IFDEF SYN_COMPILER_4_UP}
  {$IFNDEF SYN_CLX}
    property OnEndDock;
  {$ENDIF}
{$ENDIF}
    property OnEndDrag;
    property OnEnter;
    property OnExit;
    property OnKeyDown;
    property OnKeyPress;
    property OnKeyUp;
    property OnMouseDown;
    property OnMouseMove;
    property OnMouseUp;
{$IFDEF SYN_COMPILER_4_UP}
  {$IFNDEF SYN_CLX}
    property OnStartDock;
  {$ENDIF}
{$ENDIF}
    property OnStartDrag;
    // TCustomSynEdit properties
    property BookMarkOptions;
    property BorderStyle;
    property ExtraLineSpacing;
    property Gutter;
    property HideSelection;
    property Highlighter;
    property InsertCaret;
    property InsertMode;
    property Keystrokes;
    property MaxScrollWidth;
    property MaxUndo;
    property Options;
    property OverwriteCaret;
    property ReadOnly;
    property RightEdge;
    property RightEdgeColor;
    property ScrollBars;
    property SearchEngine;
    property SelectedColor;
    property SelectionMode;
    property TabWidth;
    property WantTabs;
    // TCustomSynEdit events
    property OnChange;
    property OnCommandProcessed;
    property OnDropFiles;
    property OnGutterClick;
    property OnGutterGetText;
    property OnGutterPaint;
    property OnPaint;
    property OnPlaceBookmark;
    property OnProcessCommand;
    property OnProcessUserCommand;
    property OnReplaceText;
    property OnSpecialLineColors;
    property OnStatusChange;
    property OnPaintTransient;
  end;

implementation

constructor TCustomDBSynEdit.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  FDataLink := TFieldDataLink.Create;
  FDataLink.Control := Self;
  FDataLink.OnDataChange := DataChange;
  FDataLink.OnEditingChange := EditingChange;
  FDataLink.OnUpdateData := UpdateData;
end;

destructor TCustomDBSynEdit.Destroy;
begin
  FDataLink.Free;
  FDataLink := nil;
  inherited Destroy;
end;

{*****************}
{$IFNDEF SYN_CLX}
procedure TCustomDBSynEdit.CMEnter(var Msg: TCMEnter);
begin
  SetEditing(True);
  inherited;
end;
{$ENDIF}

{*****************}
{$IFNDEF SYN_CLX}
procedure TCustomDBSynEdit.CMExit(var Msg: TCMExit);
begin
  try
    FDataLink.UpdateRecord;
  except
    SetFocus;
    raise;
  end;
  SetEditing(False);
  inherited;
end;
{$ENDIF}

{*****************}
{$IFNDEF SYN_CLX}
procedure TCustomDBSynEdit.CMGetDataLink(var Msg: TMessage);
begin
  Msg.Result := Integer(FDataLink);
end;
{$ENDIF}

procedure TCustomDBSynEdit.DataChange(Sender: TObject);
begin
  if FDataLink.Field <> nil then begin
    if FBeginEdit then
    begin
      FBeginEdit := False;
      Exit;
    end;
{$IFDEF SYN_COMPILER_3_UP}
    if FDataLink.Field.IsBlob then
      LoadMemo
    else
{$ENDIF}
      Text := FDataLink.Field.Text;
    if Assigned(FLoadData) then
      FLoadData(Self);
  end else begin
    if csDesigning in ComponentState then
      Text := Name
    else
      Text := '';
  end;
end;

procedure TCustomDBSynEdit.DragDrop(Source: TObject; X, Y: Integer);
begin
  FDataLink.Edit;
  inherited;
end;

procedure TCustomDBSynEdit.EditingChange(Sender: TObject);
begin
  if FDataLink.Editing then begin
    if Assigned(FDataLink.DataSource)
      and (FDataLink.DataSource.State <> dsInsert)
    then
      FBeginEdit := True;
  end;
end;

procedure TCustomDBSynEdit.ExecuteCommand(Command: TSynEditorCommand;
  AChar: char; Data: pointer);
begin
  // cancel on [ESC]
  if (Command = ecChar) and (AChar = #27) then
    FDataLink.Reset
  // set editing state if editor command
  else begin
    if (Command >= ecEditCommandFirst) and (Command <= ecEditCommandLast) then
      FDataLink.Edit;
  end;
  inherited;
end;

function TCustomDBSynEdit.GetDataField: string;
begin
  Result := FDataLink.FieldName;
end;

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

function TCustomDBSynEdit.GetField: TField;
begin
  Result := FDataLink.Field;
end;

function TCustomDBSynEdit.GetReadOnly: Boolean;
begin
  Result := FDataLink.ReadOnly;
end;

procedure TCustomDBSynEdit.Loaded;
begin
  inherited Loaded;
  if csDesigning in ComponentState then
    DataChange(Self);
  FOldOnChange := OnChange;
  OnChange := NewOnChange;
end;

procedure TCustomDBSynEdit.LoadMemo;
{$IFDEF SYN_COMPILER_3_UP}
var
  BlobStream: TStream;
{$ELSE}
var
  BlobStream: TBlobStream;
  BlobField: TBlobField;
{$ENDIF}
begin
  try
{$IFDEF SYN_COMPILER_3_UP}
    BlobStream := FDataLink.DataSet.CreateBlobStream(FDataLink.Field, bmRead);
{$ELSE}
    BlobField := FDataLink.Field as TBlobField;
    BlobStream := TBlobStream.Create(BlobField, bmRead);
{$ENDIF}
    Lines.BeginUpdate;
    Lines.LoadFromStream(BlobStream);
    Lines.EndUpdate;
    BlobStream.Free;
    Modified := false;
    ClearUndo;
  except
    { Memo too large }
    on E: EInvalidOperation do
      Lines.Text := Format('(%s)', [E.Message]);
  end;
  EditingChange(Self);
end;

procedure TCustomDBSynEdit.NewOnChange(Sender: TObject);
begin
  FDataLink.Modified;
  if assigned(FOldOnChange) then
    FOldOnChange(Sender);
end;

procedure TCustomDBSynEdit.Notification(AComponent: TComponent;
  Operation: TOperation);
begin
  inherited Notification(AComponent, Operation);
  if (Operation = opRemove) and (FDataLink <> nil) and (AComponent = DataSource)
  then
    DataSource := nil;
end;

procedure TCustomDBSynEdit.SetDataField(const Value: string);
begin
  FDataLink.FieldName := Value;
end;

procedure TCustomDBSynEdit.SetDataSource(Value: TDataSource);
begin
  if not (FDataLink.DataSourceFixed and (csLoading in ComponentState)) then
    FDataLink.DataSource := Value;
  if Value <> nil then
    Value.FreeNotification(Self);
end;

procedure TCustomDBSynEdit.SetEditing(Value: Boolean);
begin
  if fEditing <> Value then begin
    fEditing := Value;
{$IFDEF SYN_COMPILER_3_UP}
    if not Assigned(FDataLink.Field) or not FDataLink.Field.IsBlob then
{$ENDIF}
      FDataLink.Reset;
  end;
end;

procedure TCustomDBSynEdit.SetReadOnly(Value: Boolean);
begin
  FDataLink.ReadOnly := Value;
end;

procedure TCustomDBSynEdit.UpdateData(Sender: TObject);
{$IFDEF SYN_COMPILER_3_UP}
var
  BlobStream: TStream;
{$ENDIF}
begin
{$IFDEF SYN_COMPILER_3_UP}
  if FDataLink.Field.IsBlob then
  begin
    BlobStream := FDataLink.DataSet.CreateBlobStream(FDataLink.Field, bmWrite);
    Lines.SaveToStream(BlobStream);
    BlobStream.Free;
  end else
{$ENDIF}
    FDataLink.Field.AsString := Text;
end;

{$IFDEF SYN_CLX}
function TCustomDBSynEdit.EventFilter(Sender: QObjectH;
  Event: QEventH): Boolean;
begin
  Result := inherited EventFilter( Sender, Event );
  case QEvent_type(Event) of
    QEventType_FocusIn:
      SetEditing( True );
    QEventType_FocusOut:
      SetEditing( False );
  end;
end;
{$ENDIF}

end.