CComObjectGlobal Class
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This class manages a reference count on the module containing your Base object.
Syntax
template<class Base>
class CComObjectGlobal : public Base
Parameters
Base
Your class, derived from CComObjectRoot or CComObjectRootEx, as well as from any other interface you want to support on the object.
Members
Public Constructors
| Name | Description |
|---|---|
| CComObjectGlobal::CComObjectGlobal | The constructor. |
| CComObjectGlobal::~CComObjectGlobal | The destructor. |
Public Methods
| Name | Description |
|---|---|
| CComObjectGlobal::AddRef | Implements a global AddRef. |
| CComObjectGlobal::QueryInterface | Implements a global QueryInterface. |
| CComObjectGlobal::Release | Implements a global Release. |
Public Data Members
| Name | Description |
|---|---|
| CComObjectGlobal::m_hResFinalConstruct | Contains the HRESULT returned during construction of the CComObjectGlobal object. |
Remarks
CComObjectGlobal manages a reference count on the module containing your Base object. CComObjectGlobal ensures your object will not be deleted as long as the module is not released. Your object will only be removed when the reference count on the entire module goes to zero.
For example, using CComObjectGlobal, a class factory can hold a common global object that is shared by all its clients.
Inheritance Hierarchy
Base
CComObjectGlobal
Requirements
Header: atlcom.h
CComObjectGlobal::AddRef
Increments the reference count of the object by 1.
STDMETHOD_(ULONG, AddRef)();
Return Value
A value that may be useful for diagnostics and testing.
Remarks
By default, AddRef calls _Module::Lock, where _Module is the global instance of CComModule or a class derived from it.
CComObjectGlobal::CComObjectGlobal
The constructor. Calls FinalConstruct and then sets m_hResFinalConstruct to the HRESULT returned by FinalConstruct.
CComObjectGlobal(void* = NULL));
Remarks
If you have not derived your base class from CComObjectRoot, you must supply your own FinalConstruct method. The destructor calls FinalRelease.
CComObjectGlobal::~CComObjectGlobal
The destructor.
CComObjectGlobal();
Remarks
Frees all allocated resources and calls FinalRelease.
CComObjectGlobal::m_hResFinalConstruct
Contains the HRESULT from calling FinalConstruct during construction of the CComObjectGlobal object.
HRESULT m_hResFinalConstruct;
CComObjectGlobal::QueryInterface
Retrieves a pointer to the requested interface pointer.
STDMETHOD(QueryInterface)(REFIID iid, void** ppvObject);
Parameters
iid
[in] The GUID of the interface being requested.
ppvObject
[out] A pointer to the interface pointer identified by iid, or NULL if the interface is not found.
Return Value
A standard HRESULT value.
Remarks
QueryInterface only handles interfaces in the COM map table.
CComObjectGlobal::Release
Decrements the reference count of the object by 1.
STDMETHOD_(ULONG, Release)();
Return Value
In debug builds, Release returns a value that may be useful for diagnostics and testing. In non-debug builds, Release always returns 0.
Remarks
By default, Release calls _Module::Unlock, where _Module is the global instance of CComModule or a class derived from it.
See Also
CComObjectStack Class
CComAggObject Class
CComObject Class
Class Overview