如何确定 Office 加载项是在 Excel 还是 Excel Online 下运行？

Question

I'm writing an Office Add-in (formerly, Apps for Office). I'm using office.js and in some point of code I want to check if the app is running in excel (desktop software) or running on the web (Excel Online)

Something like:

if (Office.IsRunningOnWeb){
    // Do something.
}

Answer 1

@Mehrandvd, if I may ask, what do you need this distinction for (eg,. what would you do different based on knowing that you're in Excel Online vs. the Desktop)? I work on the Office.js APIs, so I'm happy to channel your feedback to my team, if you can provide some specifics.

If you need this distinction for feature detection, I would recommend checking the API Requirement sets instead, via a new (but back-ported to all endpoints) API, Office.context.requirements.isSetSupported(name, version) . Please see my answer at Neat ways to get environment (ie Office version) .

If it's due to some API differences you're seeing between the Excel desktop vs Online versions, the goal is for the APIs to behave the same across endpoints, so it may be a bug. If you let me know the specifics, I can follow up.

Re. the answer mentioned by @Afshin -- it may work, but just be aware that it's not public API but rather the internal workings that you're testing against, so there's a chance that this approach would stop working in the future... The only publically-exposed namespace is Office (and, with the new Excel and Word APIs released in Sept. 2015 , also Excel and Word and OfficeExtension ).

Hope this helps!

~ Michael Zlatkovsky

Developer on Office Extensibility team, MSFT

PS: Please use the office-js tag for tagging these sorts of questions in the future; this is the stackoverflow tag that the Office Extensibility team at Microsoft actively looks at.

Answer 2

You can use document type:

if (Microsoft.Office.WebExtension.context.document instanceof OSF.DDA.ExcelWebAppDocument) {
                                    //Your app running on the web
                                }

if (Microsoft.Office.WebExtension.context.document instanceof OSF.DDA.ExcelDocument) {
                                    //Your app running in excel
                                }

Answer 3

The question is how do you do it, not why would you want to. There are numerous reasons why you might want to differentiate. Put in this check as follows:

if (window.top == window) {
//the add-in is not running in Excel Online
}
else
{
//the add-in is running in Excel online
}

Answer 4

Inspired by Sturb 's answer, the following works with ExcelApi 1.10 & 1.12

if (window.top.window == window) {
  // Add-in is running in Excel desktop
} else {
  // Add-in is running in Excel online
}