CComUnkArray Class
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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.