How can I tell the difference between source and published .NET code?

I am looking at some inherited code that I have not touched in about a year. The original designer had me first publish locally before uploading the published code to the internet server. Now I am looking a number of backed up source folders as well bas backed up published folders. I should have done a better job at naming the folders, I guess. Now I wonder: How can I tell the difference between source and published .NET code? Is there some easy way to see if some folder that contains only published code is lacking a file or xml setting?

Is the .csproj file or the .sln file part of the code pushed to the server when you publish?