Plug-ins in C# - The Code Project - C# Programming: "Introduction:

First things first: I wrote this article mainly because I’ve found a complete lack of comprehensive information on the subject. Sure there are projects out there that show you how to make a simple plug-in that lets you do something dumb like feed it two numbers, and then one plug-in may add the two numbers together and return the result, while the other plug-in may multiply them instead. This is where I began, and is not bad reading as a prep tutorial to this tutorial. It might not be a bad idea to understand those tutorials first. However, when I began to search for how to bring GUIs into the plug-ins, I was completely lost. My aim is to show you how to do this, and provide some clear explanations. This tutorial will not be a step by step guide to making the program, as if you have the tutorial, you should also have the source code for the Tutorial project. I feel it unnecessary to go through this all, so instead I will only be covering some explanations on the code that is tricky."