Copy code with syntax highlights - Visual Studio and Notepad++

To copy from Visual Studio, first paste in Word, then copy from Word and paste in target

To copy from Notepad++, use the NppExport plugin
(I found the solution here)
Select your code, then: Plugins -> NppExport -> Copy all formats to clipboard
To create a shortcut for this command, you can use Settings -> Shortcut mapper...
I use Ctrl+Shift+C for this command

Update: See a better solution for C# here