The FileHelpers are an easy to use .NET library written in C#. Is designed to read/write data from flat files with fixed length or delimited records (CSV). Also has support to import/export data from different data storages (Excel, Access, SqlServer)
Code on GitHub: https://github.com/MarcosMeli/FileHelpers
Nice and Easy to use.
I had used this library 3 years ago for creating several different types of flat files (.txt) in a variety of different formats. This library filled all of the complicated requirements. I need it again for a different project, so I'm downloading it again today. 5 stars!
I just used this on a fixed length file parsing project and it worked great.