Why can't pass Marshaled interface as integer(or pointer)
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by cemick
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Published on 2010-03-18T11:18:35Z
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2010/03/18
11:21 UTC
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I passed ref of interface from Visio Add-ins to MyCOMServer (http://stackoverflow.com/questions/2455183/interface-marshalling-in-delphi).I have to pass interface as pointer in internals method of MyCOMServer. I try to pass interface to internal method as pointer of interface, but after back cast when i try call method of interface I get exception. Simple example(Fisrt block execute without error, but At Second block I get Exception after addressed to property of IVApplication interface):
procedure TMyCOMServer.test(const Interface_:IDispatch); stdcall;
var
IMy:_IMyInterface;
V: Variant;
Str: String;
I: integer;
Vis: IVApplication;
begin
......
Self.QuaryInterface(_IMyInterface,IMy);
str := IA.ApplicationName;
V := Integer(IMy);
i := V;
Pointer(IMy) := Pointer(i);
str := IMy.SomeProperty; // normal completion
str := (Interface_ as IVApplication).Path;
V := Interface_;
I := V;
Pointer(Vis) := Pointer(i);
str := Vis.Path; // 'access violation at 0x76358e29: read of address 0xfeeefeee'
end;
Why I can't do like this?
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