unit Unit1;

interface

uses

  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,

  ExtCtrls, jpeg, Menus;

type

  TForm1 = class(TForm)

    Image1: TImage;

    MainMenu1: TMainMenu;

    N1: TMenuItem;

    dd1: TMenuItem;

    procedure FormShow(Sender: TObject);

  private

      FClientInstance : TFarProc;

      FPrevClientProc : TFarProc;

      Procedure ClientWndProc(Var Message: TMessage); // 自定义的窗口过程

    { Private declarations }

  public

    { Public declarations }

  end;

var

  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.ClientWndProc(var Message: TMessage);

var

      Dc : hDC;

      Row : Integer;

      Col : Integer;

begin

  with Message do

    case Msg of

    WM_ERASEBKGND:// 当要重会背景时

    begin

      Dc := TWMEraseBkGnd(Message).DC; // 消息自带DC

      // 铺图象

      // 计算并会制行和高总共要画的数量。

      for Row :=  to ClientHeight div Image1.Picture.Height do

        for Col :=  to ClientWidth div Image1.Picture.Width do

          BitBlt(Dc,Col * Image1.Picture.Width, Row * Image1.Picture.Height

                 ,Image1.Picture.Width, Image1.Picture.Height

                 ,Image1.Picture.Bitmap.Canvas.Handle, , , SRCCOPY);

      Result := ; // 到此结束，并不继续传递

    end;

    else // 传递其他消息

      Result := CallWindowProc(FPrevClientProc,ClientHandle,Msg,wParam,lParam);

  end;

end;

procedure TForm1.FormShow(Sender: TObject);

begin

  FClientInstance := MakeObjectInstance(ClientWndProc);//将自定义过程的地址入口存入PClientInstance中

  FPrevClientProc := Pointer(GetWindowLong(ClientHandle, GWL_WNDPROC));//记录消息位置

  SetWindowLong(ClientHandle,GWL_WNDPROC,LongInt(FClientInstance));//重新载入窗口的消息并继续处理。

end;

end.

unit Unit1;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, ComCtrls;

type

  TForm1 = class(TForm)

    PageControl1: TPageControl;

    TabSheet1: TTabSheet;

    TabSheet2: TTabSheet;

    procedure FormCreate(Sender: TObject);

  private

    { Private declarations }

    procedure EditWndProc(var Message: TMessage);

  public

    { Public declarations }

  end;

var

  Form1: TForm1;

  EditHandle: THandle;

  EditPointer:Pointer;

implementation

{$R *.dfm}

procedure TForm1.EditWndProc(var Message: TMessage);

begin

  case Message.Msg of

      WM_KEYDOWN  :                          //如果是按键消息

      begin

        if Message.WParam in [,] then   //如果是左右箭头

          Exit;

      end;

   end;

   Message.Result:=CallWindowProc(EditPointer, EditHandle, Message.Msg, Message.WParam, Message.LParam);

end;

procedure TForm1.FormCreate(Sender: TObject);

Var P:Pointer;

begin

  EditHandle:=PageControl1.Handle;

  if EditHandle<> then

  begin

    EditPointer := Pointer(GetWindowLong(EditHandle, GWL_WNDPROC));

    P := Classes.MakeObjectInstance(EditWndProc);

    SetWindowLong(EditHandle, GWL_WNDPROC, Longint(P));

  end;

end;