Go into preferences -> Packages and type 'CSharp'
I've used Lisp in the picture as I already installed CSharp so it won't show up any more.
Pregunta
I've just started using https://atom.io/ on OSX
If I open a C# file it doesn't syntax highlight.
I've found https://github.com/atom/language-csharp
Do I just clone that and copy it into /Applications/Atom.app/Contents/Resources/app/node_modules ?
Solución
Go into preferences -> Packages and type 'CSharp'
I've used Lisp in the picture as I already installed CSharp so it won't show up any more.
Otros consejos
If you've installed the command line utilities, you can also "apm install language-csharp" from the command line.
Omnisharp is recommended for C# support in Atom. Here's the package installation commands from their page.
apm install language-csharp
apm install autocomplete-plus
apm install omnisharp-atom
This was added to the core packages in February 2015, so if you're running the latest version of Atom it should be already installed.
Here's the pull request: https://github.com/atom/atom/pull/5408