Должен ли я определять все члены при определении интерфейса Windows API на C #? Могу ли я определить только те методы, которые собираюсь использовать?

Например, это полное определение интерфейса IFileOpenDialog , интерфейса оболочки Windows, взято с сайта Pinvoke :

[ComImport, Guid ( "d57c7288-d4ad-4768-be02-9d969532d960" ), InterfaceType ( ComInterfaceType.InterfaceIsIUnknown )]
interface IFileOpenDialog : IFileDialog
{
// Defined on IModalWindow - repeated here due to requirements of COM interop layer
// --------------------------------------------------------------------------------
[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime ), PreserveSig]
int Show ( [In] IntPtr parent );

// Defined on IFileDialog - repeated here due to requirements of COM interop layer
[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetFileTypes ( [In] uint cFileTypes, [In] COMDLG_FILTERSPEC[] rgFilterSpec );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetFileTypeIndex ( [In] uint iFileType );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetFileTypeIndex ( out uint piFileType );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void Advise ( [In, MarshalAs ( UnmanagedType.Interface )] IFileDialogEvents pfde, out uint pdwCookie );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void Unadvise ( [In] uint dwCookie );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetOptions ( [In] FOS fos );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetOptions ( out FOS pfos );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetDefaultFolder ( [In, MarshalAs ( UnmanagedType.Interface )] IShellItem psi );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetFolder ( [In, MarshalAs ( UnmanagedType.Interface )] IShellItem psi );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetFolder ( [MarshalAs ( UnmanagedType.Interface )] out IShellItem ppsi );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetCurrentSelection ( [MarshalAs ( UnmanagedType.Interface )] out IShellItem ppsi );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetFileName ( [In, MarshalAs ( UnmanagedType.LPWStr )] string pszName );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetFileName ( [MarshalAs ( UnmanagedType.LPWStr )] out string pszName );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetTitle ( [In, MarshalAs ( UnmanagedType.LPWStr )] string pszTitle );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetOkButtonLabel ( [In, MarshalAs ( UnmanagedType.LPWStr )] string pszText );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetFileNameLabel ( [In, MarshalAs ( UnmanagedType.LPWStr )] string pszLabel );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetResult ( [MarshalAs ( UnmanagedType.Interface )] out IShellItem ppsi );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void AddPlace ( [In, MarshalAs ( UnmanagedType.Interface )] IShellItem psi, NativeMethods.FDAP fdap );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetDefaultExtension ( [In, MarshalAs ( UnmanagedType.LPWStr )] string pszDefaultExtension );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void Close ( [MarshalAs ( UnmanagedType.Error )] int hr );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetClientGuid ( [In] ref Guid guid );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void ClearClientData ( );

// Not supported:  IShellItemFilter is not defined, converting to IntPtr
[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetFilter ( [MarshalAs ( UnmanagedType.Interface )] IntPtr pFilter );

// Defined by IFileOpenDialog
// ---------------------------------------------------------------------------------
[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetResults ( [MarshalAs ( UnmanagedType.Interface )] out IShellItemArray ppenum );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void GetSelectedItems ( [MarshalAs ( UnmanagedType.Interface )] out IShellItemArray ppsai );
}

Если я собираюсь использовать только два метода из этого интерфейса, могу ли я определите это как:

[ComImport, Guid ( "d57c7288-d4ad-4768-be02-9d969532d960" ), InterfaceType ( ComInterfaceType.InterfaceIsIUnknown )]
interface IFileOpenDialog : IFileDialog
{
// Defined on IModalWindow - repeated here due to requirements of COM interop layer
// --------------------------------------------------------------------------------
[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime ), PreserveSig]
int Show ( [In] IntPtr parent );

[MethodImpl ( MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime )]
void SetOptions ( [In] FOS fos );
}

Это будет работать? Или мне нужно определить полный интерфейс для всех методов?