How would I convert a System (.net) C++\\CLI
String^
into a MFC C++ LPCTSTR
string.
It is very easy to get a LPCTSTR
You might want to try Marshal::StringToHGlobalUni, Marshal::StringToHGlobalAuto or Marshal::StringToHGlobalAnsi.
Remember the allocated unmanaged strings will need to be freed with Marshal::FreeHGlobal.
If you have Visual Studio 2008 or above, you should be able to do this using the C++/CLI marshaling library, like so:
#include <msclr\marshal.h>
using namespace System;
using namespace msclr::interop;
...
String^ cliString;
marshal_context context;
LPCTSTR cstr = context.marshal_as<const TCHAR*>(cliString);
More information on marshaling between types on MSDN: Overview of Marshaling in C++