Voice from the field
Donwloads: Demo Project
As office developers, I am sure you have already create tons of the VSTO and COM addins. I do remember the pain when merge some COM addins to VSTO platform. Sweet and spicy time back in days! We growing up and dropped some scaring workarounds and made refactored code easy and more supportable.
Now Microsoft come up with new "idea" - Office Apps. Web platform! Really? Refactoring? Again?
They said, "VSTO still been supportable. Like now you can still find working COM addin solutions. The main goal is make your Addin work on new platform including Mac and Office Online". Stop! Wait a minute Mac? Really?
Yes. It perfectly doable with Office Apps. It is just a embed web browser inside of the Word/Excel instance locally or new window in Office Online. The embed browser is IE (stop! do not tell me this!). It will works on Mac OS as well.
But how we workaround exited limitation? Yes. There is a way you simply can implement whatever you need in VSTO and make you Web Page call to the VSTO to get value and return it back. Crazy? Yes it does. Do not blame me it just temporary work around and will be eliminated as soon as API will extend according our need. Soon or likely soon. Let say in one day in the future you will get it out of box ... but now the workaround.
In attached file you can find working example of integration between Office App and VSTO. That integration is made through Ajax calls to the self-hosted Web API. Web API implemented as standalone MVC project and can be tested and hosted separately.
Let me give you brief details before get your hands dirty.
Here is a result of the execution this POC. Enjoy J