Searching for messages with categories in Office 365 REST API

Question

I'm trying to find all messages that have a non-empty category list, using Office 365 REST API, using the following request:

/api/v2.0/me/messages?$search=%22Categories:-[]%22

This doesn't seem to work though: it returns an empty result set. When I run the same query in Outlook 2016 UI, it does return results. Is it not supported or is their something wrong with the query?

Answer 1

As my test, using the following format can get the non-empty category list. endpointUri + "/Me/Messages?$search=%22category:%22". The search field is 'category', and add nothing behind the colon. Hope it helps.