Displaying C# code in Wordpress.com
Just edit your aricles in html mode and enclose your code within these tags.
[sourcecode language="css"][/sourcecode]Example:
[sourcecode language="javascript"] // javascript hello world program alert('Hello, World !!');[/sourcecode]Note: You need to specify correct language identifier for the language attribute as shown above.
The [sourcecode] tag usually works fine for C#, but for me it often breaks when I post XAML code.
Instead I use this page to format my code. The result looks nice (you can see it on my blog), but it requires the "Custom CSS" option ($15/year).
EDIT: actually the [sourcecode] tag works fine, and I'm now using it in all my posts