Cross platform compatibility of MS Office Add-ins

1
votes

We have a customised tab on MS Office Ribbon, built in Visual Studio and distributed via VSTO and Click Once and loads as a .com object.

But its currently limited to Windows.

MS is now promoting "Office Add-ins" that claim to be multi-platform.

We use Excel and Powerpoint.

Although the browser based "task pane" is clearly multi platform and add in buttons are multi platform, can an entire custom fluent tab and multiple buttons be made available across multiple platforms?

If we Migrate to 365 and use Office add ins and the javascript api what features are unavailable currently when compared to the traditional COM objects? Can we utilise OpenXML for example?

MS doesn't seem to list what's not available or not possible yet... The Javascript api seems to be quite limited.

The main platforms to target are: Windows, iPad, Web Browser (Office for the web)

Android and iOS may be required in the future.

1
office365vstoopenxmloffice-addins

1 Answers

1
votes

Although the browser based "task pane" is clearly multi platform and add in buttons are multi platform, can an entire custom fluent tab and multiple buttons be made available across multiple platforms?

Yes, you can add your custom UI to the ribbon. But it is very limited in comparing to the COM add-ins. There are predefined actions for the ribbon buttons - custom action, open a task pane of your add-in and etc.

If we Migrate to 365 and use Office add ins and the javascript api what features are unavailable currently when compared to the traditional COM objects? Can we utilise OpenXML for example?

It is easier to say what is available because they are still very limited in comparing to COM add-ins. In case of Excel, take a look at the Office Add-ins platform overview page for more information about web add-ins. In JS you can deal with open XML documents, see Open XML SDK for JavaScript.

To understand what is possible and what is not, I'd recommend playing with the Office JavaScript APIs with the Script Lab tool -- a sandbox for running and exploring the APIs.

Also you can read about comparison of both technologies in the Selecting an API or technology for developing solutions for Outlook article. It is related to Outlook, but most things are common between Office hosts - deployment, APIs and etc.

The major difference comes from the underlying technologies. In case of native add-ins (the COM technology) there is no limitation on using various APIs or components.