BackLINQ

BackLINQ allows applications written in C# 3.0, but which need to target .NET Framework 2.0 and/or 3.x, to reap the benefits and expressivity of LINQ to Objects and lambda expressions. It provides a complete and tested implementation of the LINQ Standard Query Operators.

The Short of BackLINQ

Once you have gotten used to expressing queries on objects using LINQ, it is hard to go back and write them in an imperative and verbose style. Some folks may still need to target .NET Framework 2.0 and with the multi-targeting capability of Visual Studio 2008, it is possible to continue to use C# 3.0 without requiring users to install .NET Framework 3.5 (which is required to use LINQ to Objects). This is where BackLINQ comes in and what it was designed to solve.

BackLINQ gives you:

A set of C# files that you can add to your project as part of your binaries; no need to add a reference to yet another library.
An implementation of System.Linq.Enumerable and a few other supporting types that you can take with you.
Hundreds of unit tests to guarantee 100% behavioral compatibility. Also, all of the original 101 LINQ Samples from Microsoft have been tested to run identically on BackLINQ.
Last but not least, a liberally licensed open source project where you can control your fate.