The other day I was in a conference call and someone asked if you could close OneNote via the API. In fact you cannot do this via the API but when I was talking to some of the developers for the team they said that you could just send Windows messages to OneNote telling it to close. Well I thought that sounded like a good idea. I am no expert on how to program this so I set out this evening to learn how to do this and do it with C# since I think that is what most developers will be using to program with OneNote.
I knew to start off looking for stuff about FindWindow which was in the user32.dll library and I knew about SendMessage as well but I wasn't sure how I was going to get this. I first landed on this page: Kill any application with system menu using C# - The Code Project - C# Programming. However this was if you knew the name of your application and the problem is that OneNote might have a few of them open so I had to keep searching. I then went to MSDN: EnumWindows Function which looked promising since I wanted to use this. However MSDN didn't have any code samples for this : (
Then I ended up here Enumerating Windows which had some good information but not quite what I was looking for. Then I found this page:Capturing the Running IE Instances in C#. This had some great information.
So I ended up with the following code, okay well I just found out that you can't easily post code on a blog...grrr this sucks. Please get the file here: KillOneNote.
If you have questions please let me know and I hope this works for you!