Adding an item to the windows right click context menu

So, I haven't found a lot of info on this subject. I know the items are reffered to as shell extension, and how you can add one by editing the registry. But nothing about adding one through code.

Anyone know how you 'd add your app to the right click explorer menu, in C++? (yes I know you can use code to edit the registry and add your app there, but I'm thinking maybe microsoft has some functions nested in it's API to make the process faster)