Maybe this api is useful to you: http://cciast.codeplex.com/
Microsoft Research Common Compiler Infrastructure (CCI) is a set of libraries and an application programming interface (API) that supports some of the functionality that is common to compilers and related programming tools. CCI is used primarily by applications that create, modify or analyze .NET portable executable (PE) and debug (PDB) files.
Or you can load all with Assembly.LoadFrom(path) and call to Assembly.GetExportedTypes()