This interface provides methods that allow an application to obtain the handle to the various windows that participate in in-place activation, and also to enter and exit context-sensitive help mode.

Several other in-place activation interfaces are derived from this interface. Containers and objects must implement and use these interfaces in order to support in-place activation.

C# Definition:

/// <summary>
/// Implemented and used by containers and objects to obtain window handles
/// and manage context-sensitive help.
/// </summary>
/// <remarks>
/// The IOleWindow interface provides methods that allow an application to obtain
/// the handle to the various windows that participate in in-place activation,
/// and also to enter and exit context-sensitive help mode.
/// </remarks>
[ComImport]
[Guid("00000114-0000-0000-C000-000000000046")]
[InterfaceType (ComInterfaceType.InterfaceIsIUnknown)]
public interface IOleWindow
{
    /// <summary>
    /// Returns the window handle to one of the windows participating in in-place activation
    /// (frame, document, parent, or in-place object window).
    /// </summary>
    /// <param name="phwnd">Pointer to where to return the window handle.</param>
    void GetWindow (out IntPtr phwnd) ;

    /// <summary>
    /// Determines whether context-sensitive help mode should be entered during an
    /// in-place activation session.
    /// </summary>
    /// <param name="fEnterMode"><c>true</c> if help mode should be entered;
    /// <c>false</c> if it should be exited.</param>
    void ContextSensitiveHelp ([In, MarshalAs(UnmanagedType.Bool)] bool fEnterMode) ;
}

VB Definition:

   ''' <summary>
   ''' Implemented and used by containers and objects to obtain window handles
   ''' and manage context-sensitive help.
   ''' </summary>
   ''' <remarks>
   ''' The IOleWindow interface provides methods that allow an application to obtain
   ''' the handle to the various windows that participate in in-place activation,
   ''' and also to enter and exit context-sensitive help mode.
   ''' </remarks>
   <ComImport(), Guid("00000114-0000-0000-C000-000000000046"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)> _
   Public Interface IOleWindow
      ''' <summary>
      ''' Returns the window handle to one of the windows participating in in-place activation
      ''' (frame, document, parent, or in-place object window).
      ''' </summary>
      ''' <param name="phwnd">Pointer to where to return the window handle.</param>
      Sub GetWindow(<System.Runtime.InteropServices.Out()> ByRef phwnd As IntPtr)

      ''' <summary>
      ''' Determines whether context-sensitive help mode should be entered during an
      ''' in-place activation session.
      ''' </summary>
      ''' <param name="fEnterMode"><c>true</c> if help mode should be entered;
      ''' <c>false</c> if it should be exited.</param>
      Sub ContextSensitiveHelp(<[In](), MarshalAs(UnmanagedType.Bool)> ByVal fEnterMode As Boolean)
   End Interface