소유자 윈도우 찾기2 (GetWindow)

#include <windows.h>

LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
LRESULT CALLBACK ChildProc(HWND,UINT,WPARAM,LPARAM);
LRESULT CALLBACK PopupProc(HWND,UINT,WPARAM,LPARAM);
HINSTANCE g_hInst;
HWND hWndMain;
LPSTR lpszClass="WinRelation";

int APIENTRY WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance
     ,LPSTR lpszCmdParam,int nCmdShow)
{
    HWND hWnd;
    MSG Message;
    WNDCLASS WndClass;
    g_hInst=hInstance;
    
    WndClass.cbClsExtra=0;
    WndClass.cbWndExtra=0;
    WndClass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);
    WndClass.hCursor=LoadCursor(NULL,IDC_ARROW);
    WndClass.hIcon=LoadIcon(NULL,IDI_APPLICATION);
    WndClass.hInstance=hInstance;
    WndClass.lpfnWndProc=(WNDPROC)WndProc;
    WndClass.lpszClassName=lpszClass;
    WndClass.lpszMenuName=NULL;
    WndClass.style=CS_HREDRAW | CS_VREDRAW;
    RegisterClass(&WndClass);

    WndClass.hbrBackground=(HBRUSH)GetStockObject(LTGRAY_BRUSH);
    WndClass.hCursor=LoadCursor(NULL,IDC_IBEAM);
    WndClass.lpfnWndProc=(WNDPROC)ChildProc;
    WndClass.lpszClassName="ChildClass";
    RegisterClass(&WndClass);

    WndClass.hbrBackground=(HBRUSH)GetStockObject(DKGRAY_BRUSH);
    WndClass.hCursor=LoadCursor(NULL,IDC_CROSS);
    WndClass.lpfnWndProc=(WNDPROC)PopupProc;
    WndClass.lpszClassName="PopupClass";
    RegisterClass(&WndClass);

    hWnd=CreateWindow(lpszClass,lpszClass,WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,
        NULL,(HMENU)NULL,hInstance,NULL);
    ShowWindow(hWnd,nCmdShow);
    hWndMain=hWnd;
    
    while(GetMessage(&Message,0,0,0)) {
        TranslateMessage(&Message);
        DispatchMessage(&Message);
    }
    return Message.wParam;
}

HWND hChild, hPopup, h1, h2, h11, h12, h21, h22;
LRESULT CALLBACK WndProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    HWND hParent, hOwner;
    char str[256];

    switch(iMessage) {
    case WM_CREATE:
        // 차일드 윈도우 g_hInst->parent windows handle
        hChild=CreateWindow("ChildClass",NULL,WS_CHILD | WS_VISIBLE,
            10,10,200,200,
            hWnd,(HMENU)0,g_hInst,NULL);

        // 팝업 윈도우
        hPopup=CreateWindow("PopupClass","팝업 윈도우",WS_POPUPWINDOW | WS_CAPTION | WS_VISIBLE,
            10,10,200,200,
            hWnd,(HMENU)0,g_hInst,NULL);
    
        // 버튼
        h1=CreateWindow("button","버튼1",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
            220,20,100,25,hWnd,(HMENU)0,g_hInst,NULL);    // WM_COMMAND 0번 이벤트
        h2=CreateWindow("button","버튼2",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
            220,50,100,25,hWnd,(HMENU)1,g_hInst,NULL);    // WM_COMMAND 1번 이벤트
        return 0;
    case WM_PAINT:
        hdc=BeginPaint(hWnd, &ps);
        wsprintf(str,"My Handle is %d",hWnd);
        TextOut(hdc,10,220,str,strlen(str));
        EndPaint(hWnd, &ps);
        return 0;
    case WM_LBUTTONDOWN:
        hParent=GetParent(hWnd);
        hOwner=GetWindow(hWnd,GW_OWNER);
        wsprintf(str,"Parent=%d, Owner=%d",hParent, hOwner);
        MessageBox(hWnd,str,"결과",MB_OK);
        return 0;
    case WM_COMMAND:
        switch (LOWORD(wParam)) {
        case 0:
            hParent=GetParent(h1);                                    // 부모 handle을 가져오기
            hOwner=GetWindow(h1,GW_OWNER);                            // 소유자 h1 handle 얻기
            wsprintf(str,"Parent=%d, Owner=%d",hParent, hOwner);
            MessageBox(hWnd,str,"결과",MB_OK);
            return 0;
        }
        return 0;
    case WM_DESTROY:
        PostQuitMessage(0);
        return 0;
    }
    return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}

LRESULT CALLBACK ChildProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    HWND hParent, hOwner;
    char str[256];

    switch(iMessage) {
    case WM_CREATE:
        h11=CreateWindow("button","버튼11",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
            20,20,100,25,hWnd,(HMENU)0,g_hInst,NULL);
        h12=CreateWindow("button","버튼12",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
            20,50,100,25,hWnd,(HMENU)1,g_hInst,NULL);
        return 0;
    case WM_PAINT:
        hdc=BeginPaint(hWnd, &ps);
        wsprintf(str,"My Handle is %d",hWnd);
        TextOut(hdc,20,80,str,strlen(str));
        EndPaint(hWnd, &ps);
        return 0;
    case WM_LBUTTONDOWN:
        hParent=GetParent(hWnd);
        hOwner=GetWindow(hWnd,GW_OWNER);
        wsprintf(str,"Parent=%d, Owner=%d",hParent, hOwner);
        MessageBox(hWnd,str,"결과",MB_OK);
        return 0;
    case WM_COMMAND:
        switch (LOWORD(wParam)) {
        case 0:
            hParent=GetParent(h11);
            hOwner=GetWindow(h11,GW_OWNER);
            wsprintf(str,"Parent=%d, Owner=%d",hParent, hOwner);
            MessageBox(hWnd,str,"결과",MB_OK);
            return 0;
        }
        return 0;
    }
    return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}

LRESULT CALLBACK PopupProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
    HDC hdc;
    PAINTSTRUCT ps;
    HWND hParent, hOwner;
    char str[256];

    switch(iMessage) {
    case WM_CREATE:
        h21=CreateWindow("button","버튼21",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
            20,20,100,25,hWnd,(HMENU)0,g_hInst,NULL);
        h22=CreateWindow("button","버튼22",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
            20,50,100,25,hWnd,(HMENU)1,g_hInst,NULL);
        return 0;
    case WM_PAINT:
        hdc=BeginPaint(hWnd, &ps);
        wsprintf(str,"My Handle is %d",hWnd);
        TextOut(hdc,20,80,str,strlen(str));
        EndPaint(hWnd, &ps);
        return 0;
    case WM_LBUTTONDOWN:
        hParent=GetParent(hWnd);
        hOwner=GetWindow(hWnd,GW_OWNER);
        wsprintf(str,"Parent=%d, Owner=%d",hParent, hOwner);
        MessageBox(hWnd,str,"결과",MB_OK);
        return 0;
    case WM_COMMAND:
        switch (LOWORD(wParam)) {
        case 0:
            hParent=GetParent(h21);
            hOwner=GetWindow(h21,GW_OWNER);
            wsprintf(str,"Parent=%d, Owner=%d",hParent, hOwner);
            MessageBox(hWnd,str,"결과",MB_OK);
            return 0;
        }
        return 0;
    }
    return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}