I just finished my copy of C# in depth by Jon Skeet (published by Manning) and I highly recommend this book to ANY C# professional programmer. Jon is the author of one of the most informative blog on C#. As soon as I realized that he was writing a book on advanced topics of the language, I wanted to read it cover to cover. There are many, many C# books around but with Jon’s one, I was sure that I could polish my knowledge of some aspects of the language. And indeed I haven’t been disappointed.

The book covers sequentially C#2 enhancements and then C#3 enhancements. This provides a unique perspective on the language evolution, from a traditional modern OOP language to a OOP / Functional hybrid one. When programming with C#, this is not a luxury to know how to use functional constructs and especially closures. Since I discover them back in 2004 while being an early adopter of C#2, it definitely changed my coding style. When mixed with advanced language constructs such as generics, type inference, contra/co variance,…closures becomes a dramatic way to enhance your code conciseness and expressiveness. Such power doesn’t come for free and you need first some proper education. IMHO I don’t think that there is any other C# book around that has a better coverage of these aspects. An interesting Jon’s note is that delegates were initially done to implement the concept of event (i.e some kind of command, that perform an action and doesn’t return anything) and become with C#2 first and C#3 after, a premium way to implement computational stuff (i.e function, whose only reason is to return something without any side-effects).

Actually the entire LINQ cathedral sits on closures. But LINQ is not just a C#/VB.NET language artefact and is surrounded by several frameworks. C# in depth is certainly a great introduction to LINQ but to make the most of LINQ I would advise in addition the reading of a pure LINQ book, such as LINQ in Action.

Not only the content is great but also the writing. This is a concise 370 pages software book. Jon doesn’t waste space (and tree!) to explain again and again basic C# construct. Still, you’ll get some refresher on some underlying aspect of the .NET platform such value vs. reference type, with many myths dispelled. I only have 2 minor tacks: First I would have like some decompilation of some IL part with Reflector. This is how I explained some advanced aspects of C# 2 and I still think it is the best way to teach some functional flows to a pure OOP programmer. Using a tool such as Reflector is also a good reflex to have each time you have a doubt about what the compiler spit. Showing this reflex to readers is not a luxury. Second, in a world where a single using clause can thoroughly change the meaning of all code elements, I would have like A to Z code print and not just some excerpt. Here again this is how I used to write book and I still believe programmer needs full C# code file to read printed on the paper. But don’t take me wrong. C# in depth is likely the best book available today to become a better C# programmer (and that’s what you want, else you wouldn’t be on CodeBetter.com!). Go read it!