Open-Source Simple Source Codes?

Question

I was wondering if anyone can point me in the direction of a source code that implements many basic functions of C# in one easy program just to show as an example in one of my classes.  Just simple things such as functions of parse, messageboxes, dialogboxes, comboboxes, textboxes, if and case statements... etc.  Very basic stuff, I am just not sure where to go to find a very simple program such as this that has many different elements in it. If it is against the rules to ask for something like this I apologize, i just know there are many open-source places that maybe I dont know about. thanks.