通过TObject.GetInterface可以获得对象的实例实现某个接口，前提条件是必须实例化对象后才能运行GetInterface
下面的方法可获取类是否实现了某个接口，并返回接口的偏移：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | functionFindInterface(AClass: TClass; GUID:TGUID;varOffset:NativeInt):Boolean;
var
i :integer;
InterfaceTable: PInterfaceTable;
InterfaceEntry: PInterfaceEntry;
begin
whileAssigned(AClass)do
begin
InterfaceTable := AClass.GetInterfaceTable;
ifAssigned(InterfaceTable)then
begin
fori :=0toInterfaceTable.EntryCount-1do
begin
InterfaceEntry := @InterfaceTable.Entries[i];
ifInterfaceEntry.Idelphi keyword">then
begin
Offset:=InterfaceEntry.IOffset;
Exit(True);
end;
end;
end;
AClass := AClass.ClassParent;
end;
end;
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下面我们看下通过偏移量的快速获得对象的接口，以及通过接口快速获取对象：
快速获取对象的接口：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | type
TSomeObject=class(TXXX, ISomeInterface)
......
end;
var
FItemObjectOffset:NativeInt;
FindInterface(TSomeObject, ISomeInterface, FItemObjectOffset)
var
P:TSomeObject;
Intf:ISomeInterface;
....................................
PNativeInt(@Intf)^:=PNativeInt(@P)^+ FItemObjectOffset;
Intf._AddRef;
|
快速通过接口获取对象
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | type
TSomeObject=class(TXXX, ISomeInterface)
......
end;
var
FItemObjectOffset:NativeInt;
FindInterface(TSomeObject, ISomeInterface, FItemObjectOffset)
var
P:TSomeObject;
Intf:ISomeInterface;
....................................
P:=TSomeObject(Pointer(PNativeInt(@Intf)^- FItemObjectOffset));
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https://www.cnblogs.com/hezihang/p/5735897.html