Mono framework

Mono is an open source implementation of Microsoft’s .NET Framework based on the ECMA standards for C# and the Common Language Runtime.
Mono is different from .Net on linux , which is a Microsoft port of .Net to linux.
UPDATE : mono is now supported by Microsoft , who contributes to the project

Er is een NET framework /NET core versie beschikbaar die op linux runt, maar deze ondersteunt niet de desktop apps (ttz de windows desktop apps)
wel console , web apps , services e.d.
Voor native linux + net desktop apps heb je dus Mono nodig.

https://www.mono-project.com/
Er istevens een tweede open source project : Xamarin

mono-complete

Mono is a platform for running and developing applications based on the ECMA/ISO Standards. Mono is an open source effort led by Xamarin. Mono provides a complete CLR (Common Language Runtime) including compiler and runtime, which can produce and execute CIL (Common Intermediate Language) bytecode (aka assemblies), and a class library.

This is a metapackage and pulls in the Mono runtime, development tools and all libraries.
Install this package if you want to run software for Mono or Microsoft .NET which you are not installing from a Debian package.

mono-complete pulls in mono-runtime and all the available Mono libraries, including whatever Mono libraries provide database support
So you’d expect database-using .NET software to work with mono-complete.

mono-runtime only contains the .NET VM and JIT and AOT code generators.
If you only have that installed, not much .NET code will work, and database-using .NET software certainly won’t.

sudo apt-get install mono-runtime 

sudo apt-get purge --remove mono-complete sudo apt-get install mono-complete