ZForge.Win32.RemovableDriveDetector.RegisterForDeviceChange C# (CSharp) Méthode

        private void RegisterForDeviceChange(bool register, SafeFileHandle fileHandle)
        {
            if (register)
            {
                // Register for handle
                DEV_BROADCAST_HANDLE data = new DEV_BROADCAST_HANDLE();
                data.dbch_devicetype = DBT_DEVTYP_HANDLE;
                data.dbch_reserved = 0;
                data.dbch_nameoffset = 0;
                //data.dbch_data = null;
                //data.dbch_eventguid = 0;
                data.dbch_handle = fileHandle.DangerousGetHandle(); //Marshal. fileHandle;
                data.dbch_hdevnotify = (IntPtr)0;
                int size = Marshal.SizeOf(data);
                data.dbch_size = size;
                IntPtr buffer = Marshal.AllocHGlobal(size);
                Marshal.StructureToPtr(data, buffer, true);

                mDeviceNotifyHandle = Native.RegisterDeviceNotification(mRecipientHandle, buffer, 0);
            }
            else
            {
                // close the directory handle
                if (mDirHandle != IntPtr.Zero)
                {
                    Native.CloseDirectoryHandle(mDirHandle);
                    //    string er = Marshal.GetLastWin32Error().ToString();
                }

                // unregister
                if (mDeviceNotifyHandle != IntPtr.Zero)
                {
                    Native.UnregisterDeviceNotification(mDeviceNotifyHandle);
                }

                mDeviceNotifyHandle = IntPtr.Zero;
                mDirHandle = IntPtr.Zero;

                mCurrentDrive = "";
                if (mFileOnFlash != null)
                {
                    mFileOnFlash.Close();
                    mFileOnFlash = null;
                }
            }
        }