Hey, this is rigth. But my problem is when i pass by reference a std::string to an old-style DLL. It writes the result in the pointer, not in the buffer, then the buffer hold no data(unitialized data), I call c_str() an retrieves the data in the buffer with bad_data. Is there a way I can obtain the pointer? Thanks a lot.
-----Mensaje original----- De: dotnet discussion [mailto:[EMAIL PROTECTED]] En nombre de Tomas Restrepo Enviado el: jueves, 25 de abril de 2002 16:37 Para: [EMAIL PROTECTED] Asunto: Re: [DOTNET] MC++: string to System::String Miguel, > Thanks, this is the way it works. But now, I have another problem. I惴 > calling a function in an API, that have the next signature: > > void function1(out std::string* version); > > If I debug and see the value in the Watch window, I see the next version > returned value: > > version > _Bx > [+] _Buf > [+] _Ptr <- The function return the value here > > When I call version.c_str(), I obtain a pointer to the buf, that is like > a char[], but not to the ptr where the function copies the data. You're not quite right. It's just that the std::strng implementation on VC++.NET is quite different. Now, it uses a union between a char[16] and a char*. If the string it holds is less than 15 chars in length, it's held in the char array in-place, saving an allocation. Only if it's larger will an external buffer be allocated on the heap and a pointer to it stored in _Ptr. Regardless of that, you can be sure string::c_str() will return a pointer to the actual storage of the string. -- Tomas Restrepo [EMAIL PROTECTED] You can read messages from the DOTNET archive, unsubscribe from DOTNET, or subscribe to other DevelopMentor lists at http://discuss.develop.com. You can read messages from the DOTNET archive, unsubscribe from DOTNET, or subscribe to other DevelopMentor lists at http://discuss.develop.com.
