How can I add DLL plugins to my C# application?
<p>Simple question, but likely a big answer. I have a C# solution that comprises of multiple projects - I want to add the ability to drop in a DLL plugin that will "hook in" to the program and add additional functions.</p>

<p>I want to be able to have entry points, for example on a checkout screen where it calculates the price, the DLL will say "I need access to this routine/entry point" and then be able to access the pricing variables that are in the application at that moment and output to show a customized discount or something like that.</p>

<p>Can anyone recommend a way of accomplishing this?
Are there frameworks/libraries that exist to make this possible?</p>

<p>Thanks so much.</p>