How to detect whether a control is standard or active-x control?

In MFC Application, how can we differen开发者_如何学JAVAtiate whether a control is a standard control like CComboBox or it is an custom active-x control?

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You can use CWnd::GetControlUnknown:

Return Value

A pointer to the IUnknown interface of the OLE control represented by this CWnd object. If this object does not represent an OLE control, the return value is NULL.