This is the class dld : dynamic load dll Documentation.
dld.cs is the body class.
CV.cs is use to show how to use the dld class.
dll folder is use to show how to export a dll in C++.
The most important part of dll is the Entry Point, you can use the command line tools : dumpbin in visual C++ to inquire the entry point.
In cpp file, if you want to export to C#, you should be export to _stdcall. If you want to export to C or C++, you should be export to _cdecl(and you can use LoadLibrary API()).