What .NET Framework and C# version should I target with my class library?

Question

I\'m building a DLL class library - I want to make it usable by as many people as possible. Which version of the .NET Framework and which C# version should I use? Is it po

Answer 1

I vote for Erik van Brakel's answer. Also I would like to suggest that if you want to support 3.5 features like LINQ and Extension methods, you may create an additional library, say

MyLibrary.DLL

MyLibrary.LINQ.dll

thus using the same approach as MS did (when they left System.dll 2.0 version but added all new features into System.Core.dll)