IEnumConnectionPoints
A version of this page is also available for
4/8/2010
This interface enumerates connection points. Connectable objects support the following features:
- Outgoing interfaces, such as event sets
- The ability to enumerate the IIDs of the outgoing interfaces
- The ability to connect and disconnect sinks to the object for those outgoing IIDs
- The ability to enumerate the connections that exist to a particular outgoing interface
When to Implement
To support connectable objects, you need to provide four related interfaces:
- IConnectionPointContainer
- IEnumConnectionPoints
- IConnectionPoint
- IEnumConnections
The IConnectionPointContainer interface indicates the existence of the outgoing interfaces.
It provides access to an enumerator subobject with the IEnumConnectionPoints interface. It also provides a connection point subobject with the IConnectionPoint interface.
The IConnectionPoint interface provides access to an enumerator subobject with the IEnumConnections interface.
The connection point is a separate subobject to avoid circular reference counting problems.
A connectable object can be asked to enumerate its supported connection points through IConnectionPointContainer::EnumConnectionPoints.
The resulting enumerator returned from this method implements the interface IEnumConnectionPoints, through which a client can access all the individual connection point subobjects supported within the connectable object itself, where each connection point implements IConnectionPoint.
When enumerating connections through IEnumConnectionPoints, the enumerator is responsible for calling AddRef, and the caller is responsible for later calling Release when those pointers are no longer needed.
When to Use
Use the IEnumConnectionPoints interface to enumerate all the supported connection points for each outgoing IID.
Methods in Vtable Order
| IUnknown method | Description |
|---|---|
Returns pointers to supported interfaces. |
|
Increments the reference count. |
|
Decrements the reference count. |
| Method | Description |
|---|---|
Creates another enumerator that contains the same enumeration state as the current one. |
|
Enumerates the next cConnections elements in the enumerator's list, returning them in rgpcn along with the actual number of enumerated elements in pcFetched. |
|
Instructs the enumerator to position itself at the beginning of the list of elements. |
|
Instructs the enumerator to skip the next cConnections elements in the enumeration so the next call to IEnumConnectionPoints::Next does not return those elements. |
Remarks
To determine whether the platform supports this interface, see Determining Supported COM APIs.
Requirements
| Header | ocidl.h, ocidl.idl |
| Library | ole32.lib, uuid.lib |
| Windows Embedded CE | Windows CE 3.0 and later |
| Windows Mobile | Windows Mobile Version 5.0 and later |