...create a base class with a non-reference counted implementation of IUnknown?
Author: P. Below
If I want automatic garbage collection with interfaces, I use
TInterfacedObject as base class. What should I use,
if I don't want automatic destruction?
is there a similar common base class or do I
have to implement the IInterface methods myself?
I use this one:{== BaseNonRefcountIntfObjU
===========================================}
{: This unit provides a base class with a non-reference counted
implementation of IUnknown.
@author Dr. Peter Below
@desc Version 1.0 created 28 März 2002
Last modified 28 März 2002
}
{======================================================================}
unit BaseNonRefcountIntfObjU;
interface
type
{: Derive classes that need a non-reference counted IUNknown
implementation from this class. }
TNonRefcountInterfacedObject = class(TObject, IUnknown)
protected
{ IUnknown }
function QueryInterface(const IID : TGUID; out Obj): HResult;
stdcall;
function _AddRef: Integer; stdcall;
function _Release: Integer; stdcall;
end;
implementation
uses Windows;
function TNonRefcountInterfacedObject.QueryInterface(const IID : TGUID;
out Obj): HResult;
begin
if GetInterface(IID, Obj) then
Result := S_OK
else
Result := E_NOINTERFACE
end;
function TNonRefcountInterfacedObject._AddRef: integer;
begin
Result := -1 // -1 indicates no reference counting is taking
place
end;
function TNonRefcountInterfacedObject._Release: integer;
begin
Result := -1 // -1 indicates no reference counting is taking
place
end;
end { BaseNonRefcountIntfObjU }.
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