Win32 code anomaly - c++

Question

I am facing a very odd problem. Can any one tell me what is wrong with the following code-:
#include <Windows.h>
LRESULT CALLBACK WindowFunc(HWND, UINT, WPARAM, LPARAM);
char szWinName[]="MyWin";
int WINAPI WinMain(HINSTANCE hThisInst, HINSTANCE hPrevInst,
LPSTR lpszArgs, int nWinMode)
{
HWND hwnd;
MSG msg;
WNDCLASSEX wndclass;
wndclass.cbSize=sizeof(WNDCLASSEX);
wndclass.hInstance=hThisInst;
wndclass.lpszClassName=szWinName;
wndclass.lpfnWndProc=WindowFunc;
wndclass.style=0;
wndclass.hIcon=LoadIcon(NULL,IDI_APPLICATION)
wndclass.hIconSm=NULL;
wndclass.hCursor=LoadCursor(NULL,IDC_ARROW);
wndclass.lpszMenuName=NULL;
wndclass.cbClsExtra=0;
wndclass.cbWndExtra=0;
wndclass.hbrBackground=(HBRUSH) GetStockObject(LTGRAY_BRUSH);
if(!RegisterClassEx(&wndclass)) return 0;
hwnd=CreateWindow(
szWinName,
"Hello World",
WS_OVERLAPPED,
CW_USEDEFAULT,
CW_USEDEFAULT,
500,
500,
NULL,
NULL,
hThisInst,
NULL
);
ShowWindow(hwnd, nWinMode);
UpdateWindow(hwnd);
while(GetMessage(&msg, NULL, 0, 0)>0)
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WindowFunc(HWND hwnd, UINT message, WPARAM wparam,
LPARAM lparam)
{
switch(message){
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hwnd,message,wparam,lparam);
}
return 0;
}
I am getting the following window-:
As you can see there is no system menu. I do not know why this is happening. But if I replace the above code with the following code it seems to work just fine-:
#include<windows.h>
LRESULT CALLBACK WinProc(HWND,UINT,WPARAM,LPARAM);
char szWinName[]="Main Window";
int WINAPI WinMain(HINSTANCE thisInst,HINSTANCE prevInst,
LPSTR lpCmdArgs, int nMode){
HWND hwnd;
MSG msg;
WNDCLASSEX wndclass;
wndclass.cbSize=sizeof(WNDCLASSEX);
wndclass.hInstance=thisInst;
wndclass.lpszClassName=szWinName;
wndclass.lpfnWndProc=WinProc;
wndclass.style=0;
wndclass.hIcon=LoadIcon(NULL,IDI_APPLICATION)
wndclass.hIconSm=NULL;
wndclass.hCursor=LoadCursor(NULL,IDC_ARROW);
wndclass.lpszMenuName=NULL;
wndclass.cbClsExtra=0;
wndclass.cbWndExtra=0;
wndclass.hbrBackground=(HBRUSH)GetStockObject(LTGRAY_BRUSH);
if(!RegisterClassEx(&wndclass)) return 0;
hwnd=CreateWindow( szWinName,
"Hello World",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
500,
500,
NULL,
NULL,
thisInst,
NULL
);
ShowWindow(hwnd,nMode);
UpdateWindow(hwnd);
while(GetMessage(&msg,NULL,0,0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WinProc(HWND hWnd, UINT message,
WPARAM wparam, LPARAM lparam){
switch(message){
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wparam, lparam);
}
return 0;
}
Please can someone tell me what I doing wrong in the first code segment I have tried everything and not been able to find what is wrong with it. I am using a normal Win32 Project in Visual Studio 2008 Professional Edition. If anyone wants I can mail the project to them to test it out for themselves. A quick reply would be appreciated. Thank You.

Answer 1

In the bottom code segment you use WS_OVERLAPPEDWINDOW as a window style, which is what gives you the system menu. The first code segment only has WS_OVERLAPPED, which only gives you the title bar and border.