DELPHI5的MDI窗体如何加IMAGE,加了之后便看不到,如何解决?

Question

正确代码：
VAR
  MyDC : hDC;
  Ro, Co : Word;
begin
  with Message do
    case Msg of
      WM_ERASEBKGND:
        begin
          MyDC := TWMEraseBkGnd(Message).DC;
          FOR Ro := 0 TO ClientHeight DIV Image1.Picture.Height DO
            FOR Co := 0 TO ClientWIDTH DIV Image1.Picture.Width DO
              BitBlt(MyDC, Co*Image1.Picture.Width, Ro*Image1.Picture.Height,
                Image1.Picture.Width, Image1.Picture.Height,
                Image1.Picture.Bitmap.Canvas.Handle, 0, 0, SRCCOPY);
          Result := 1;
        end;
    else
      Result := CallWindowProc(FPrevClientProc, ClientHandle, Msg, wParam, lParam);
    end;
end;

Answer 1

應該是Form 的 OnCreat事件吧。

Answer 2

在kingron的主页上下载一个Delphi猛料，里面有很多有用的技巧，其中就有你提到的东西。大致上讲，应该是这样：Tfrm_Main = class(TForm)
  private
    MDIDefProc:pointer;
    MDIInstance:TFarProc;
    procedure MDIWndProc(var prmMsg:TMessage);
  protected
    procedure CreateWnd; override;
  public
  end;procedure Tfrm_Main.CreateWnd;
begin
 inherited CreateWnd;
 MDIInstance:=MakeObjectInstance(MDIWndProc); { create wrapper }
 MDIDefProc:=pointer(SetWindowLong(ClientHandle,GWL_WNDPROC,
     longint(MDIInstance)) );
end;procedure Tfrm_Main.MDIWndProc(var prmMsg: TMessage);
begin
 with prmMsg do
   if Msg = WM_ERASEBKGND then
     // Snakeguo(楠) 的代码
   else
     Result:=CallWindowProc(MDIDefProc,ClientHandle,Msg,wParam,lParam);
end;

Answer 3

unit main;interfaceuses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  OutlookBtn, ToolWin, ComCtrls, ExtCtrls, Db, ADODB;type
  Tfrmmain = class(TForm)；
  Image1: TImage;
private
    FClientInstance,FPrevClientProc : TFarProc;
    procedure ClientWndProc(VAR Message: TMessage);
    { Private declarations }
  public
    { Public declarations }
  end;var
  frmmain: Tfrmmain;
implementation
{$R *.DFM}
procedure Tfrmmain.ClientWndProc(VAR Message: TMessage);
var mydc:hdc;
    row,col:integer;
begin
 with message do
 case msg of WM_ERASEBKGND:
 begin
   MyDC := TWMEraseBkGnd(Message).DC;
   FOR Row := 0 TO ClientHeight DIV Image1.Picture.Height DO
   FOR Col := 0 TO ClientWIDTH DIV Image1.Picture.Width DO
   BitBlt(MyDC,
    Col*Image1.Picture.Width,
    Row*Image1.Picture.Height,
    Image1.Picture.Width,
    Image1.Picture.Height,
    Image1.Picture.Bitmap.Canvas.Handle,
    0,
    0,
    SRCCOPY);
    Result := 1;
    end;
    else
    Result := CallWindowProc(FPrevClientProc,ClientHandle,Msg,wParam,lParam);
   end;
   end;procedure Tfrmmain.FormCreate(Sender: TObject);
begin
   FClientInstance := MakeObjectInstance(ClientWndProc);
   FPrevClientProc := Pointer(GetWindowLong(ClientHandle,GWL_WNDPROC));
   SetWindowLong(ClientHandle,GWL_WNDPROC,LongInt(FClientInstance));
   frmmain.WindowState:=wsmaximized;
end;

Answer 4

我早解决了，不好意思，现在才来看，Movingboy(movingboy)的办法就是我用的，好了，结帐。