Is there an automatic code formatter for C#?

For Visual Studio, take a look at ReSharper. It's an awesome tool and a definite must-have. Versions after 4.0 have the code formatting and clean-up feature that you are looking for. There's also plugin integration with StyleCop, including formatting settings file.

You'll probably want Agent Smith plugin as well, for spell-checking the identifiers and comments. ReSharper supports per-solution formatting setting files, which can be checked into version control system and shared by the whole team. The keyboard shortcut for code cleanup is Ctrl + E, C.

In 'vanilla' Visual Studio, the current file can be automatically formatted with Ctrl + K, Ctrl + D, and Ctrl + K, Ctrl + F formats the selected text.

As for a runs-everywhere command line tool to be used with commit hooks, try NArrange. It's free, can process whole directories at once and runs on Mono as well as on Microsoft .NET.

Some people also use the Artistic Style command line tool, although it requires Perl and works better with C/C++ code than with C#.

Further to @Chris Karcher's answer - you can also automatically format the whole document by hitting Ctrl+K, Ctrl+D.

These formatting features work on a variety of file formats - it works wonders on ugly HTML.

Another option: NArrange;

• free
• console based (so good for commit hooks etc, but can still be used as an "External Tool" in VS)
• flexible config file

For me, Ctrl + Shift + F maps to Find in Files. When I need to format code, I highlight it and hit Ctrl + K, Ctrl + F.

I understand this doesn't really address automated formatting. I just wanted to clarify for those who may not know this feature even exists in Visual Studio.

I've heard only good things about ReSharper. It's on my to-learn list.

http://www.sourceformat.com/

This tool is around (~30$). I tried it and it works nice (with multiple languages).

I like this tool the best because it doesn't check code file for correctness. I can post code snippets from the Internet and it will translate them correctly no matter if they are in missing parts of the code. Other tools I try complain in that cases. The tool can also be integrated easily into editors as it allows command line driving.

Other tools:

http://www.polystyle.com/index.jsp

http://astyle.sourceforge.net/ (open source)

Not directly, but I use the Agent Smith plugin for R# to do this. Unfortunately, R# isn't free.

Also take a look at Microsoft StyleCop

I haven't tried this (found it through Google). It might work. http://www.semdesigns.com/Products/Formatters/CSharpFormatter.html. It's fairly cheap at USD50, but a trial is not available.

See this previous question:

Is there any tool for reformatting C# code?

Searching for [c#] astyle shows up some more previous questions too.