I needed a way to quick, free way to check what compiled in a DLL on something that built in a big project. It seemed like no matter how I built, it was getting some old code. So, I googled and some big names had some free decompilers already available. Telerik has JustDecompile, and JetBrains has dotPeek. While both were good, they had their differences.
Telerik’s JustDecompile had asked me to install some trial versions of their other software during installation, so heads up you might want to uncheck everything besides JustDecompile since it’s the only totally free item they offer in the installation. When I ran it, it was very smooth, and quick to decompile all the Dlls I threw at it. The code was well formatted and easy to transverse.
JetBrains’ dotPeek installed quick and easy, and good to go within a minute. It was a little bit slower than Telerik’s solution, but for the most part a lot faster than products I’ve seen in the past. One downside I noticed right away navigating through my code is that the formatting was off. I got a lot of “ISSUE: reference to a compiler-generated field” and other similar error messages, while Telerik’s seemed to handle everything correctly. The code that was decompiled however was closest to what I had written, which helped me recognize any errors relatively quickly vs Teleriks’, which was off on quite of a few statements (logically was the same, just the code was slightly different… ie if statement logic).
Basically, I would suggest downloading both. They are both pretty lightweight for what they do and it’s always nice to get a second set of tools to offer a different look. Both are done well and worth your time. Good luck and happy coding!