Après avoir quelqu'un crée une DLL C # en utilisant Microsoft Visual environnement de développement, comment prendre un autre programmeur de ce code, faire un nouveau projet qui comprend la DLL de la source et de faire une interface graphique utilisant la DLL API?
 
After someone creates a DLL in C# using the Microsoft Visual development environment, how would another programmer take that code, make a new project that includes the DLL's source and make a GUI that uses the DLL'S API?  

You must add the "Class Library" (DLL) to your Solution.  
To do that:
 
- click right on your solution.
- Select "Add new Project". In the browse tab of the window, select the class library (DLL) created by another user.  
 
After these operations, you can use the classes defined in the added library.  
Note, that you must prefix theses classes with the correct namespace.
 
HOPE this help