I'm looking for a linear programming solver for C#. In the other words I'm looking for a library for C# that solves linear programming problems.

I need an easy to use library (so I can learn how to use it quickly), but it would be nice if it supported some features as automatic absolute values conversion (so I don't have to program the conversion myself). It is important that the library should be for free (not necessarily open source).

Good documentation is huge advantage for me. 10%-20% worse performance is not critical for my project.

Thanks for your answers