Edit

CComUnkArray Class

  • Article

This class stores IUnknown pointers, and is designed to be used as a parameter to the IConnectionPointImpl template class.

Syntax

template<unsigned int nMaxSize>
class CComUnkArray

Parameters

nMaxSize
The maximum number of IUnknown pointers that can be held in the static array.

Members

Public Constructors

Name Description
CComUnkArray::CComUnkArray Constructor.

Public Methods

Name Description
CComUnkArray::Add Call this method to add an IUnknown pointer to the array.
CComUnkArray::begin Returns a pointer to the first IUnknown pointer in the collection.
CComUnkArray::end Returns a pointer to one past the last IUnknown pointer in the collection.
CComUnkArray::GetCookie Call this method to get the cookie associated with a given IUnknown pointer.
CComUnkArray::GetUnknown Call this method to get the IUnknown pointer associated with a given cookie.
CComUnkArray::Remove Call this method to remove an IUnknown pointer from the array.

Remarks

CComUnkArray holds a fixed number of IUnknown pointers, each an interface on a connection point. CComUnkArray can be used as a parameter to the IConnectionPointImpl template class. CComUnkArray<1> is a template specialization of CComUnkArray that has been optimized for one connection point.

The CComUnkArray methods begin and end can be used to loop through all connection points (for example, when an event is fired).

See Adding Connection Points to an Object for details on automating creation of connection point proxies.

Note

Note The class CComDynamicUnkArray is used by the Add Class wizard when creating a control which has Connection Points. If you wish to specify the number of Connection Points manually, change the reference from CComDynamicUnkArray to CComUnkArray< n >, where n is the number of connection points required.

Requirements

Header: atlcom.h

CComUnkArray::Add

Call this method to add an IUnknown pointer to the array.

DWORD Add(IUnknown* pUnk);

Parameters

pUnk
Call this method to add an IUnknown pointer to the array.

Return Value

Returns the cookie associated with the newly added pointer, or 0 if the array is not large enough to contain the new pointer.

CComUnkArray::begin

Returns a pointer to the beginning of the collection of IUnknown interface pointers.

IUnknown**
    begin();

Return Value

A pointer to an IUnknown interface pointer.

Remarks

The collection contains pointers to interfaces stored locally as IUnknown. You cast each IUnknown interface to the real interface type and then call through it. You do not need to query for the interface first.

Before using the IUnknown interface, you should check that it is not NULL.

CComUnkArray::CComUnkArray

The constructor.

CComUnkArray();

Remarks

Sets the collection to hold nMaxSize IUnknown pointers, and initializes the pointers to NULL.

CComUnkArray::end

Returns a pointer to one past the last IUnknown pointer in the collection.

IUnknown**
    end();

Return Value

A pointer to an IUnknown interface pointer.

Remarks

The CComUnkArray methods begin and end can be used to loop through all connection points, for example, when an event is fired.

IUnknown** p = m_vec.begin();
while(p != m_vec.end())
{
   // Do something with *p
   p++;
}

CComUnkArray::GetCookie

Call this method to get the cookie associated with a given IUnknown pointer.

DWORD WINAPI GetCookie(IUnknown** ppFind);

Parameters

ppFind
The IUnknown pointer for which the associated cookie is required.

Return Value

Returns the cookie associated with the IUnknown pointer, or 0 if no matching IUnknown pointer is found.

Remarks

If there is more than one instance of the same IUnknown pointer, this function returns the cookie for the first one.

CComUnkArray::GetUnknown

Call this method to get the IUnknown pointer associated with a given cookie.

IUnknown* WINAPI GetUnknown(DWORD dwCookie);

Parameters

dwCookie
The cookie for which the associated IUnknown pointer is required.

Return Value

Returns the IUnknown pointer, or NULL if no matching cookie is found.

CComUnkArray::Remove

Call this method to remove an IUnknown pointer from the array.

BOOL Remove(DWORD dwCookie);

Parameters

dwCookie
The cookie referencing the IUnknown pointer to be removed from the array.

Return Value

Returns TRUE if the pointer is removed, FALSE otherwise.

See also

CComDynamicUnkArray Class
Class Overview