Optional Methods in Control Interfaces
Implementing an interface doesn't necessarily mean implementing all methods of that interface to do anything more than return E_NOTIMPL or S_OK as appropriate. The following table identifies the methods of the interfaces listed in the What Support for an Interface Means topic that a control may implement in this manner. Any method not listed here must be fully implemented if the interface is supported.
| IOleControl | Comments |
|---|---|
| GetControlInfo, OnMnemonic |
Mandatory for controls with mnemonics. |
| IOleControl::OnAmbientPropertyChange |
Mandatory for controls that use ambient properties. |
| IOleControl::FreezeEvents |
See Event Freezing |
| IOleObject | |
| SetMoniker |
Mandatory if the control is not marked with OLEMISC_CANTLINKINSIDE |
| GetMoniker |
Mandatory if the control is not marked with OLEMISC_CANTLINKINSIDE |
| InitFromData |
Optional |
| GetClipboardData |
Optional |
| SetExtent |
Mandatory only for DVASPECT_CONTENT |
| GetExtent |
Mandatory only for DVASPECT_CONTENT |
| SetColorScheme |
Optional |
| DoVerb |
See note 1 |
| IOleInPlaceObject | |
| ContextSensitiveHelp |
Optional |
| ReactivateAndUndo |
Optional |
| IOleInPlaceActiveObject | |
| ContextSensitiveHelp |
Optional |
| IViewObject2 | |
| Freeze |
Optional |
| Unfreeze |
Optional |
| GetColorSet |
Optional |
| IPersistStream, IPersistStreamInit, IPersistMemory | |
| GetSizeMax |
See note 2 |
- A control with property pages must support IOleObject::DoVerb for the OLEIVERB_PROPERTIES and OLEIVERB_PRIMARY verbs. A control that can be active must support DoVerb for the OLEIVERB_INPLACEACTIVATE verb. A control that can be UI active must also support DoVerb for the OLEIVERB_UIACTIVATE verb.
- If a control supports IPersistStream or IPersistStreamInit and can return an accurate value, then it should do so.