I’m exploring a lot on .NET cross platform development these days. One of the option other than .NET core, is to leverage Mono framework. Mono framework and MonoDevelop IDE also helps us to develop cross-platfrom .NET applications.  Here are the steps i followed to set up Mono framework and MonoDevelop IDE on Ubuntu 18.0.4.

a)Set up mono repository for ubuntu 18.0.4

sudo apt-key adv –keyserver hkp://keyserver.ubuntu.com:80 –recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF

 
echo “deb https://download.mono-project.com/repo/ubuntu stable-bionic main” | sudo tee /etc/apt/sources.list.d/mono-official-stable.list

sudo apt update

b)Install required packages

Install the package mono-devel to compile the code.
sudo apt install mono-devel

Install the package mono-complete to install everything.
sudo apt install mono-complete

Install the package mono-dbg to get the debugging symbols for framework libraries.
sudo apt install mono-dbg

Install package referenceassemblies-pcl for PCL compilation support (this gets installed if your install mono-complete).
sudo apt install referenceassemblies-pcl

Install package ca-certificates-mono to get SSL certificates for https connection (this gets installed if your install mono-complete).

sudo apt install ca-certificates-mono

Install pakage mono-xsp4 to run ASP.NET applications.
sudo apt install mono-xsp4

c)Install monodevelop IDE

The pre-requisite for installing MonoDevelop IDE is to set up the  mono repository for ubuntu 18.0.4 (mentioned in step #a). Then proceeed to IDE installation using apt-get package manager.

sudo apt-get install monodevelop