System.Classes.TInterfacedPersistent.QueryInterface
Delphi
function QueryInterface(const IID: TGUID; out Obj): HResult; virtual; stdcall;
C++
virtual HRESULT __stdcall QueryInterface(const GUID &IID, /* out */ void *Obj);
Properties
| Type | Visibility | Source | Unit | Parent |
|---|---|---|---|---|
| function | public | System.Classes.pas System.Classes.hpp |
System.Classes | TInterfacedPersistent |
Description
Returns a reference to a specified interface if the object supports that interface.
QueryInterface implements the IInterface method, QueryInterface. This method checks whether the interfaced persistent object supports the interface identified by IID. If so, it returns a reference as the Obj parameter, automatically incrementing the reference count for the interface. If the object does not support the specified interface, it returns a non-zero value.