How can I compile two .cs files into single DLL?

Question

Say I have foo.cs and bar.cs. if I create two seperate projects for each source file and compile them to two DLLs, I have no problem in importing and using them in other projects.

What should I do if I want an output of single DLL?(with keeping separate source files) Can a DLL file have two namespaces? if not, How can I place contents of foo and bar into single namespace? (I can edit them)

Answer 1

if I create two seperate projects

Create one project with both files in it to produce one DLL as output. The namespaces can be anything you'd like, though convention suggests that classes within a project share a common root namespace.

Answer 2

You only have to add both files to the same Project.

Can a DLL file have two namespaces?

Yes. And conversely one namespace can be used in multiple DLLs.