C++ LPCONTEXTMENU::QueryContextMenu方法代码示例

BOOL CRecBinViewer::ExecCommand (LPCONTEXTMENU pCtxMenu,  LPCTSTR lpszCommand)
{
	UINT uiID = UINT (-1);
	UINT uiCommand = 0;
	UINT uiMenuFirst = 1;
	UINT uiMenuLast = 0x00007FFF;
	HMENU hmenuCtx;
	int iMenuPos = 0;
	int iMenuMax = 0;
	TCHAR szMenuItem[MAX_PATH];	
	TCHAR verb[MAX_PATH] ;

	hmenuCtx = CreatePopupMenu();
	HRESULT hr = pCtxMenu->QueryContextMenu(hmenuCtx, 0, uiMenuFirst, uiMenuLast, CMF_NORMAL);

	iMenuMax = GetMenuItemCount(hmenuCtx);
	
	for (iMenuPos = 0 ; iMenuPos < iMenuMax; iMenuPos++)
	{
		GetMenuString(hmenuCtx, iMenuPos, szMenuItem, MAX_PATH, MF_BYPOSITION) ;
	
		uiID = GetMenuItemID(hmenuCtx, iMenuPos) ;
		
		if ((uiID == -1) || (uiID == 0))
		{
			
		}
		else
		{
			hr = pCtxMenu->GetCommandString(uiID - 1, GCS_VERB, NULL, (LPSTR)verb, MAX_PATH);
			if (FAILED (hr))
			{
				verb[0] = TCHAR ('\0') ;
			}
			else
			{
				if (0 == _tcsicmp (verb, lpszCommand))				
					uiCommand = uiID - 1;				
			}			
		}
	}
	
	if ((UINT)-1 != uiCommand)
	{
		CMINVOKECOMMANDINFO cmi;			
		ZeroMemory(&cmi, sizeof(CMINVOKECOMMANDINFO));
		cmi.cbSize			= sizeof(CMINVOKECOMMANDINFO);
		cmi.fMask			= CMIC_MASK_FLAG_NO_UI;
		cmi.hwnd			= m_hWnd;				
		cmi.lpVerb			= (LPSTR)MAKEINTRESOURCE (uiCommand);
		cmi.nShow			= SW_SHOWNORMAL;		
		hr = pCtxMenu->InvokeCommand(&cmi);			
		if (SUCCEEDED (hr))		
			return TRUE;		
	}

	return false;
}

UINT CShellContextMenu::ShowContextMenu(QWidget * pParentWidget, QPoint pt, QMenu* pMenu )
{
        HWND hWnd = pParentWidget->winId();
        int iMenuType = 0;	// to know which version of IContextMenu is supported
	LPCONTEXTMENU pContextMenu;	// common pointer to IContextMenu and higher version interface
   
	if (!GetContextMenu ((void**) &pContextMenu, iMenuType))	
		return (0);	// something went wrong

	if (!m_hMenu)
	{
		DestroyMenu( m_hMenu );
		m_hMenu = CreatePopupMenu ();
	}

        int i;
        QList<QAction*> actionList = pMenu->actions();
        for( i=0; i<actionList.count(); ++i )
        {
           QString s = actionList.at(i)->text();
           if (!s.isEmpty())
              AppendMenuW( m_hMenu, MF_STRING, i+1, (LPCWSTR)s.utf16() );
        }
        AppendMenuW( m_hMenu, MF_SEPARATOR, i+1, L"" );

	// lets fill the our popupmenu  
	pContextMenu->QueryContextMenu (m_hMenu, GetMenuItemCount (m_hMenu), MIN_ID, MAX_ID, CMF_NORMAL | CMF_EXPLORE);
 
	// subclass window to handle menurelated messages in CShellContextMenu 
	WNDPROC OldWndProc;
	if (iMenuType > 1)	// only subclass if its version 2 or 3
	{
		OldWndProc = (WNDPROC) SetWindowLongPtr (hWnd, GWLP_WNDPROC, (LONG_PTR) HookWndProc);
		if (iMenuType == 2)
			g_IContext2 = (LPCONTEXTMENU2) pContextMenu;
		else	// version 3
			g_IContext3 = (LPCONTEXTMENU3) pContextMenu;
	}
	else
		OldWndProc = NULL;

	UINT idCommand = TrackPopupMenu (m_hMenu,TPM_RETURNCMD | TPM_LEFTALIGN, pt.x(), pt.y(), 0, pParentWidget->winId(), 0);

	if (OldWndProc) // unsubclass
		SetWindowLongPtr (hWnd, GWLP_WNDPROC, (LONG_PTR) OldWndProc);

	if (idCommand >= MIN_ID && idCommand <= MAX_ID)	// see if returned idCommand belongs to shell menu entries
	{
		InvokeCommand (pContextMenu, idCommand - MIN_ID);	// execute related command
		idCommand = 0;
	}
	
	pContextMenu->Release();
	g_IContext2 = NULL;
	g_IContext3 = NULL;

	return (idCommand);
}

UINT CShellContextMenu::ShowContextMenu(HWND hWnd, CPoint pt)
{
	int iMenuType = 0;	// to know which version of IContextMenu is supported
	LPCONTEXTMENU pContextMenu;	// common pointer to IContextMenu and higher version interface

	if(!GetContextMenu((LPVOID*)&pContextMenu, iMenuType))	
		return 0;	// something went wrong

	if(!m_Menu)
	{
		delete m_Menu;
		m_Menu = NULL;
		m_Menu = new CMenu;
		m_Menu->CreatePopupMenu();
	}

	// lets fill the popupmenu 
	pContextMenu->QueryContextMenu(m_Menu->m_hMenu, m_Menu->GetMenuItemCount(), ID_SHELLCONTEXTMENU_MIN, ID_SHELLCONTEXTMENU_MAX, CMF_NORMAL | CMF_EXPLORE);

	// subclass window to handle menurelated messages in CShellContextMenu 
	WNDPROC OldWndProc;
	if(iMenuType > 1)	// only subclass if its version 2 or 3
	{
		OldWndProc = (WNDPROC) SetWindowLong(hWnd, GWL_WNDPROC, (DWORD) HookWndProc);
		if(iMenuType == 2)
			g_IContext2 = (LPCONTEXTMENU2) pContextMenu;
		else	// version 3
			g_IContext3 = (LPCONTEXTMENU3) pContextMenu;
	}
	else
		OldWndProc = NULL;

	UINT idCommand = m_Menu->TrackPopupMenu(TPM_RETURNCMD | TPM_LEFTALIGN, pt.x, pt.y, hWnd);

	if(OldWndProc) // unsubclass
		SetWindowLong(hWnd, GWL_WNDPROC, (DWORD) OldWndProc);

	if(idCommand >= ID_SHELLCONTEXTMENU_MIN && idCommand <= ID_SHELLCONTEXTMENU_MAX)
	{
		InvokeCommand(pContextMenu, idCommand - ID_SHELLCONTEXTMENU_MIN);
		idCommand = 0;
	}

	pContextMenu->Release();
	g_IContext2 = NULL;
	g_IContext3 = NULL;

	return idCommand;
}

UINT CShellContextMenu::ShowContextMenu(CWnd *pWnd, CPoint pt)
{
	int iMenuType = 0;	// to know which version of IContextMenu is supported
	LPCONTEXTMENU pContextMenu;	// common pointer to IContextMenu and higher version interface
   
	if (!GetContextMenu ((void**) &pContextMenu, iMenuType))	
		return (0);	// something went wrong

	if (m_Menu)
	{
		delete m_Menu;
		m_Menu = NULL;
	}
	m_Menu = new CMenu;
	m_Menu->CreatePopupMenu ();
	// lets fill the our popupmenu  
	pContextMenu->QueryContextMenu (m_Menu->m_hMenu, m_Menu->GetMenuItemCount (), MIN_ID, MAX_ID, CMF_NORMAL | CMF_EXPLORE);
 
	// subclass window to handle menurelated messages in CShellContextMenu 
	WNDPROC OldWndProc;
	if (iMenuType > 1)	// only subclass if its version 2 or 3
	{
		OldWndProc = (WNDPROC) SetWindowLong (pWnd->m_hWnd, GWL_WNDPROC, (DWORD) HookWndProc);
		if (iMenuType == 2)
			g_IContext2 = (LPCONTEXTMENU2) pContextMenu;
		else	// version 3
			g_IContext3 = (LPCONTEXTMENU3) pContextMenu;
	}
	else
		OldWndProc = NULL;

	UINT idCommand = m_Menu->TrackPopupMenu (TPM_RETURNCMD | TPM_LEFTALIGN, pt.x, pt.y, pWnd);

	if (OldWndProc) // unsubclass
		SetWindowLong (pWnd->m_hWnd, GWL_WNDPROC, (DWORD) OldWndProc);

	if (idCommand >= MIN_ID && idCommand <= MAX_ID)	// see if returned idCommand belongs to shell menu entries
	{
		InvokeCommand (pContextMenu, idCommand - MIN_ID);	// execute related command
		idCommand = 0;
	}
	
	pContextMenu->Release();
	g_IContext2 = NULL;
	g_IContext3 = NULL;

	return (idCommand);
}

UINT CShellContextMenu::ShowContextMenu(CWnd *pWnd, POINT pt)
{
	int iMenuType = 0;	// to know which version of IContextMenu is supported
	LPCONTEXTMENU pContextMenu;	// common pointer to IContextMenu and higher version interface
   
	if (!GetContextMenu ((void**) &pContextMenu, iMenuType))	
		return (0);	// something went wrong

    if (!m_Menu)
    {
        delete m_Menu;
        m_Menu = NULL;
        m_Menu = new CMenu;
        m_Menu->CreatePopupMenu ();
        m_Menu->AppendMenu(MF_STRING, WM_MENU_FILE,_T("打开文件所在目录"));

        // lets fill the our popupmenu
        pContextMenu->QueryContextMenu(m_Menu->m_hMenu, m_Menu->GetMenuItemCount(), MIN_ID, MAX_ID, CMF_NORMAL | CMF_EXPLORE);
    }

	if (iMenuType > 1)	// only subclass if its version 2 or 3
	{
		if (iMenuType == 2)
			g_IContext2 = (LPCONTEXTMENU2) pContextMenu;
		else	// version 3
			g_IContext3 = (LPCONTEXTMENU3) pContextMenu;
	}


	UINT idCommand = m_Menu->TrackPopupMenu (TPM_RETURNCMD | TPM_LEFTALIGN, pt.x, pt.y, pWnd);

	if (idCommand >= MIN_ID && idCommand <= MAX_ID)	// see if returned idCommand belongs to shell menu entries
	{
		InvokeCommand (pContextMenu, idCommand - MIN_ID);	// execute related command
		idCommand = 0;
	}
	
	pContextMenu->Release();
	g_IContext2 = NULL;
	g_IContext3 = NULL;

	return (idCommand);
}

BOOL showContextMenu (HWND hDlg, TCHAR* FName, WNDPROC menuProc)
{
	TCHAR* FileName = PathFindFileName (FName);
	TCHAR FilePath [MAX_PATH];
	lstrcpy (FilePath, FName);
	*PathFindFileName (FilePath) = L'\0';
	
	LPSHELLFOLDER DesktopFolder;
	if (NOERROR != SHGetDesktopFolder (&DesktopFolder))
	{
		return FALSE;
	}
	
	LPITEMIDLIST ParentPidl;
	ULONG Eaten;
	if (S_OK != DesktopFolder->ParseDisplayName (hDlg, 0, FilePath, &Eaten, &ParentPidl, 0))
	{
		return FALSE;
	}
	
	LPSHELLFOLDER ParentFolder;
	if (S_OK != DesktopFolder->BindToObject (ParentPidl, 0, IID_IShellFolder, (void**)&ParentFolder))
	{
		return FALSE;
	}
	
	LPITEMIDLIST Pidl;
	if (S_OK != ParentFolder->ParseDisplayName (hDlg, 0, FileName, &Eaten, &Pidl, 0))
	{
		return FALSE;
	}	

	LPCONTEXTMENU CM;
	if (S_OK != ParentFolder->GetUIObjectOf (hDlg, 1, (LPCITEMIDLIST*)&Pidl, IID_IContextMenu, 0, (void**)&CM))
	{
		return FALSE;
	}
	
	HMENU hMenu = CreatePopupMenu ();
	if (hMenu == NULL) 
	{
		return FALSE;
	}
	
	CM->QueryContextMenu (hMenu, 0, 1, 0x7FFF, CMF_EXTENDEDVERBS | CMF_EXPLORE);
	
	WNDPROC defWndProc = (WNDPROC) SetWindowLong (hDlg, GWL_WNDPROC, (LONG)menuProc);
	SetProp (hDlg, L"defWndProc", (HANDLE) defWndProc);
	
	POINT pt;
	GetCursorPos (&pt);
	int Cmd = TrackPopupMenu (hMenu,
		TPM_LEFTALIGN | TPM_LEFTBUTTON | TPM_RIGHTBUTTON | TPM_RETURNCMD,
		pt.x, pt.y, 0, hDlg, 0);


	SetWindowLong (hDlg, GWL_WNDPROC, (LONG) RemoveProp (hDlg, L"defWndProc"));
		
	if (Cmd)
	{
		// Set up a CMINVOKECOMMANDINFO structure.
		CMINVOKECOMMANDINFO CI;
		ZeroMemory (&CI, sizeof(CMINVOKECOMMANDINFO));
		CI.cbSize = sizeof (CMINVOKECOMMANDINFO);
		CI.hwnd = hDlg;
		CI.lpVerb = (LPCSTR) MAKEINTRESOURCE(Cmd - 1);
		CI.lpParameters = "";
		CI.lpDirectory = "";
		CI.nShow = SW_SHOWNORMAL;
		CM->InvokeCommand (&CI);
	}
	
	return DestroyMenu (hMenu);
}

//.........这里部分代码省略.........
                        }
                        break;
                    default:
                        {
                        }
                    }
                }
                m_pidlManager.Delete( pItem );
                pItem = NULL;
            }
        }
        else if( pNmhdr->code == NM_RCLICK )
        {
            LPITEMIDLIST* ppIdl = NULL;
            int nSelCount = ListView_GetSelectedCount(m_hWnd);
            if ( nSelCount > 0 )
            {
                ppIdl = (LPITEMIDLIST*)_Module.m_Allocator.Alloc( sizeof(LPITEMIDLIST)*nSelCount );
                int iIndex = ListView_GetNextItem( m_hWnd, -1, LVIS_SELECTED );
                LV_ITEM item = {0};
                item.iSubItem = 0;
                item.mask = LVIF_PARAM;
                int _i = 0;
                while( iIndex >= 0 
                    && _i < nSelCount )
                {    
                    item.iItem = iIndex;
                    ListView_GetItem( m_hWnd, &item );
                    ppIdl[_i] = m_pidlManager.Copy( ITEMLISTPTR(item.lParam) );
                    ++_i;
                    iIndex = ListView_GetNextItem( m_hWnd, -1, LVIS_SELECTED );
                }
            }
            LPCONTEXTMENU pMenu = NULL;
            HRESULT hr = E_FAIL;
            hr = m_pFolder->GetUIObjectOf( m_hWnd, nSelCount, \
                (LPCITEMIDLIST*)ppIdl, IID_IContextMenu, NULL, (void**)&pMenu );
            if ( FAILED(hr)
                || !pMenu)
            {
                LOG(_T("IID_IContextMenu Failed"));
                if ( nSelCount > 0 )
                {
                    for ( int _i = 0; _i < nSelCount; ++_i )
                    {
                        m_pidlManager.Delete( ppIdl[_i] );
                    }
                    _Module.m_Allocator.Free( ppIdl );
                }
                return S_OK;
            }
            HMENU hMenu = ::CreatePopupMenu();
            if ( !hMenu )
            {
                if ( nSelCount > 0 )
                {
                    for ( int _i = 0; _i < nSelCount; ++_i )
                    {
                        m_pidlManager.Delete( ppIdl[_i] );
                    }
                    _Module.m_Allocator.Free( ppIdl );
                }
                return S_OK;
            }
            hr = pMenu->QueryContextMenu( hMenu, 0, 10, 32767, CMF_NORMAL | CMF_EXPLORE );
            if ( FAILED(hr) )
            {
                if ( nSelCount > 0 )
                {
                    for ( int _i = 0; _i < nSelCount; ++_i )
                    {
                        m_pidlManager.Delete( ppIdl[_i] );
                    }
                    _Module.m_Allocator.Free( ppIdl );
                }
                DestroyMenu( hMenu );
                return hr;
            }
            POINT point = {0};
            GetCursorPos( &point );
            UINT command = (UINT)TrackPopupMenu ( hMenu, TPM_RETURNCMD | TPM_LEFTALIGN, point.x, point.y, 0, m_hWnd, NULL );
            CMINVOKECOMMANDINFO cmi = {0};
            cmi.cbSize = sizeof (CMINVOKECOMMANDINFO);
            cmi.lpVerb = (LPSTR) MAKEINTRESOURCE (command-10);
            cmi.nShow = SW_SHOWNORMAL;
            pMenu->InvokeCommand( &cmi );
            pMenu->Release();
            if ( nSelCount > 0 )
            {
                for ( int _i = 0; _i < nSelCount; ++_i )
                {
                    m_pidlManager.Delete( ppIdl[_i] );
                }
                _Module.m_Allocator.Free( ppIdl );
            }
            DestroyMenu( hMenu );
        }
    }
    TRACE_RETURN S_OK;
}

//.........这里部分代码省略.........
Carries out the command associated with a context menu item. 

Returns NOERROR if successful, or an OLE-defined error code otherwise. 

lpici	-	Address of a CMINVOKECOMMANDINFO structure containing information about 
			the command. 
			
			 typedef struct _CMInvokeCommandInfo{ 
				DWORD cbSize; 
				DWORD fMask; 
				HWND hwnd; 
				LPCSTR lpVerb; 
				LPCSTR lpParameters; 
				LPCSTR lpDirectory; 
				int nShow; 
				DWORD dwHotKey; 
				HANDLE hIcon; 
			} CMINVOKECOMMANDINFO, *LPCMINVOKECOMMANDINFO; 

			Contains information about a context menu command. 

			cbSize			-	Contains the size of this structure, in bytes. 
			fMask			-	Zero, or one or more of the following flags: 
								CMIC_MASK_HOTKEY	-	The dwHotKey member is valid.  
								CMIC_MASK_ICON		-	The hIcon member is valid.  
								CMIC_MASK_FLAG_NO_UI-	The system is prevented from 
														displaying user interface 
														elements (for example, error 
														messages) while carrying out 
														a command.  

			hwnd			-	Handle of the window that is the owner of the context 
								menu. An extension can also use this handle as the 
								owner of any message boxes or dialog boxes it displays. 
			lpVerb			-	A 32-bit value that contains zero in the high-order 
								word and a menu-identifier offset of the command to 
								carry out in the low-order word. The shell specifies 
								this value (using the MAKEINTRESOURCE macro) when the 
								user chooses a menu command. If the high-order word 
								is not zero, this member is the address of a 
								null-terminated string specifying the 
								language-independent name of the command to carry out. 
								This member is typically a string when a command is 
								being activated by an application. The system provides 
								predefined constant values for the following command 
								strings. 

								Value				String  
								CMDSTR_NEWFOLDER	"NewFolder"  
								CMDSTR_VIEWDETAILS  "ViewDetails"  
								CMDSTR_VIEWLIST		"ViewList"  

			lpParameters	-	Optional parameters. This member is always NULL for 
								menu items inserted by a shell extension. 
			lpDirectory		-	Optional working directory name. This member is always 
								NULL for menu items inserted by a shell extension. 
			nShow			-	Set of SW_ values to pass to the ShowWindow function 
								if the command displays a window or starts an 
								application. 
			dwHotKey		-	Optional hot key to assign to any application 
								activated by the command. If the fMask parameter does 
								not specify CMIC_MASK_HOTKEY, this member is ignored. 
			hIcon			-	Icon to use for any application activated by the 
								command. If the fMask member does not specify 
								CMIC_MASK_ICON, this member is ignored. 


The shell calls this method when the user chooses a command that the handler added 
to a context menu. This method may also be called by an application without any 
corresponding user action. 
*/
	HMENU hMenu=::CreatePopupMenu();
	if(hMenu==NULL)
	{
		TRACE(_T("COXShellNamespaceNavigator::GetObjectContextMenu: CreatePopupMenu() failed\n"));
		return NULL;
	}

	hResult=lpcm->QueryContextMenu(hMenu,0,1,0x7fff,dwFlags);
	if(FAILED(hResult))  
	{
		TRACE(_T("COXShellNamespaceNavigator::GetObjectContextMenu: QueryContextMenu() failed\n"));
		::DestroyMenu(hMenu);
		return NULL;
	}
	
	hResult=lpcm->InvokeCommand(&cmici);

	::DestroyMenu(hMenu);

	lpcm->Release();

	if(FAILED(hResult))  
	{
		TRACE(_T("COXShellNamespaceNavigator::InvokeCommand: InvokeCommand() failed\n"));
		return FALSE;
	}

	return TRUE;
}

HMENU COXShellNamespaceNavigator::
	GetObjectContextMenu(const LPSHELLFOLDER lpParentFolder,
	const LPITEMIDLIST lpRelativeIDL, DWORD dwFlags) const
{
	// We can request IContextMenu interface using 
	// IShellFolder::GetUIObjectOf method.
	//
/*
HRESULT GetUIObjectOf(
    HWND hwndOwner,
    UINT cidl,
    LPCITEMIDLIST *apidl,
    REFIID riid,
    UINT *prgfInOut,
    LPVOID *ppvOut
   );	

Retrieves an OLE interface that can be used to carry out actions on the specified 
file objects or folders. 

Returns NOERROR if successful, E_NOINTERFACE if the interface is not supported, or an 
OLE-defined error value otherwise. 

hwndOwner		-	Handle to the owner window that the client should specify if it 
					displays a dialog box or message box. 
cidl			-	Number of file objects or subfolders specified in the apidl 
					parameter. 
apidl			-	Address of an array of pointers to ITEMIDLIST structures, each of 
					which uniquely identifies a file object or subfolder relative to 
					the parent folder. Each item identifier list must contain exactly 
					one SHITEMID structure followed by a terminating zero. 
riid			-	Identifier of the COM interface object to return. This can be any 
					valid interface identifier that can be created for an item. The 
					most common identifiers used by the shell are listed in the 
					comments at the end of this reference. 
prgfInOut		-	Reserved. 
ppvOut			-	Address that receives the interface pointer. If an error occurs, 
					a NULL pointer is returned in this address. 

If cidl is greater than one, the GetUIObjectOf implementation should only succeed if 
it can create one object for all items specified in apidl. If the implementation 
cannot create one object for all items, this method should fail. 

The following are the most common interface identifiers the shell uses when 
requesting an interface from this method. The list also indicates if cidl can be 
greater than one for the requested interface. 

Interface Identifier	Allowed cidl Value  
IContextMenu			The cidl parameter can be greater than or equal to one.  
IContextMenu2			The cidl parameter can be greater than or equal to one.  
IDataObject				The cidl parameter can be greater than or equal to one.  
IDropTarget				The cidl parameter can only be one.  
IExtractIcon			The cidl parameter can only be one.  
IQueryInfo				The cidl parameter can only be one.  
*/
	LPCONTEXTMENU lpcm;
    HRESULT hResult=lpParentFolder->
		GetUIObjectOf(m_pOwnerWnd!=NULL ? m_pOwnerWnd->GetSafeHwnd() : NULL, 1,
		(const struct _ITEMIDLIST**)&(lpRelativeIDL),IID_IContextMenu,0,
		(LPVOID*)&lpcm);
	if(FAILED(hResult))  
		return NULL;

	// Use IContextMenu::QueryContextMenu method to get handle to popup menu.
	//
/*
HRESULT QueryContextMenu(
    HMENU hmenu,
    UINT indexMenu,
    UINT idCmdFirst,
    UINT idCmdLast,
    UINT uFlags
   );

Adds menu items to the specified menu. The menu items should be inserted in the menu 
at the position specified by indexMenu, and their menu item identifiers must be 
between the idCmdFirst and idCmdLast parameter values. 

Returns an HRESULT structure in which, if the method is successful, the code member 
contains the menu identifier of the last menu item added plus one. 

hmenu		-	Handle to the menu. The handler should specify this handle when 
				adding menu items. 
indexMenu	-	Zero-based position at which to insert the first menu item. 
idCmdFirst	-	Minimum value that the handler can specify for a menu item identifier. 
idCmdLast	-	Maximum value that the handler can specify for a menu item identifier. 
uFlags		-	Optional flags specifying how the context menu can be changed. Can be 
				any combination of the following values: 
				CMF_CANRENAME		-	This flag is set if the calling application 
										supports renaming of items. A context menu 
										extension or drag-and-drop handler should 
										ignore this flag. A namespace extension should 
										add a rename item to the menu if applicable.  
				CMF_DEFAULTONLY		-	This flag is set when the user is activating 
										the default action, typically by 
										double-clicking. This flag provides a hint for 
										the context menu extension to add nothing if 
										it does not modify the default item in the 
										menu. A context menu extension or 
										drag-and-drop handler should not add any menu 
//.........这里部分代码省略.........