program Project1;uses  Windows, Messages;{等待调用的过程, 用于在窗体上绘制文本}Procedure OnPaint(h: HDC);const  s = 'CodeGear Delphi 2007';begin  TextOut(h, 10, 10, PChar(s), Length(s));end;{窗口回调过程}function WndProc(wnd: HWND; msg: UINT; wParam: Integer; lParam: Integer): Integer; stdcall;var  Handle: HDC;  ps: PAINTSTRUCT;begin  case msg of    WM_PAINT: begin        Handle := BeginPaint(wnd, ps);        OnPaint(Handle);        EndPaint(wnd, ps);        result := 0;     end;    WM_DESTROY: begin        PostQuitMessage(0);        result := 0;      end;   else      Result := DefWindowProc(wnd, msg, wParam, lParam);   end;end;{主程序}var  hWnd       : THandle;  Msg        : TMsg;  MyWndClass : TWndClass;begin   MyWndClass.style         := CS_HREDRAW or CS_VREDRAW;   MyWndClass.lpfnWndProc   := @WndProc;   MyWndClass.cbClsExtra    := 0;   MyWndClass.cbWndExtra    := 0;   MyWndClass.hInstance     := HInstance;   MyWndClass.hIcon         := LoadIcon(0, IDI_QUESTION);   MyWndClass.hCursor       := LoadCursor(0, IDC_ARROW);   MyWndClass.hbrBackground := HBRUSH(GetStockObject(WHITE_BRUSH));   MyWndClass.lpszMenuName  := nil;   MyWndClass.lpszClassName := 'MyWindowClass';   RegisterClass(MyWndClass);   hWnd := CreateWindow('MyWindowClass', '这是窗口标题', WS_OVERLAPPEDWINDOW,      100, 100, 250, 150, 0, 0, HInstance, nil);   ShowWindow(hWnd, SW_SHOWNORMAL);   UpdateWindow(hWnd);   while(GetMessage(Msg, 0, 0, 0)) do   begin      TranslateMessage(Msg);      DispatchMessage(Msg);   end;end.