vb.net - Mixing C# & VB In The Same Project

Question

Can you mix vb and c# files in the same project for a class library? Is there some setting that makes it possible?

I tried and none of the intellisense works quite right, although the background compiler seems to handle it well enough (aside from the fact that I, then, had 2 classes in the same namespace with the same name and it didn't complain).

We're trying to convert from VB to C# but haven't finished converting all the code. I have some new code I need to write, but didn't really want to make a new project just for it.

Answer 1

No, you can't. An assembly/project (each project compiles to 1 assembly usually) has to be one language. However, you can use multiple assemblies, and each can be coded in a different language because they are all compiled to CIL.

It compiled fine and didn't complain because a VB.NET project will only actually compile the .vb files and a C# project will only actually compile the .cs files. It was ignoring the other ones, therefore you did not receive errors.

Edit: If you add a .vb file to a C# project, select the file in the Solution Explorer panel and then look at the Properties panel, you'll notice that the Build Action is 'Content', not 'Compile'. It is treated as a simple text file and doesn't even get embedded in the compiled assembly as a binary resource.

Edit: With asp.net websites you may add c# web user control to vb.net website