CIRCCOLL Sample: Demonstrates a Collection/Enumeration
The CIRCOLL sample shows how to implement a collection/enumeration of objects using ATL.
The CIRCCOLL attributes sample is the attributed version of this sample.
This sample code is provided to illustrate a concept and should not be used in applications or Web sites, as it may not illustrate the safest coding practices. Microsoft assumes no liability for incidental or consequential damages should the sample code be used for purposes other than as intended.
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Three object classes are implemented: the collection creator, the collection, and the object inside the collection. Only the collection creator has a coclass associated with it (see Circcoll.idl for the coclass declaration). The collection creator has a method to return a collection of circle objects. The collection object implements the Item, Count, and _NewItem methods, so that the object can be manipulated from Visual Basic using both the For...Next and For Each... syntax.
This sample uses the following keywords:
AddRef; ATLASSERT; ATLTRACE; BEGIN_COM_MAP; BEGIN_OBJECT_MAP; CComCoClass; CComObject::CreateInstance; CComObjectRoot; CComVariant; COM_INTERFACE_ENTRY; DECLARE_NOT_AGGREGATABLE; DECLARE_REGISTRY; END_COM_MAP; END_OBJECT_MAP; glBegin; glEnd; glNormal3d; glPolygonMode; glVertex2d; glVertex3d; IConnectionPointContainerImpl::FindConnectionPoint; IConnectionPointImpl::Advise; IDispatchImpl; ISupportErrorInfo; OBJECT_ENTRY; QueryInterface; Release; USES_CONVERSION; VariantCopy; VariantInit