Parse / Find Results in Facebook Group Graph API Result? PHP

I have a Facebook users' ID in a variable, let's say $fbid. What would be the most efficient way to check to see if they are in a certain Facebook Group?

I'd prefer to check it using the Group Graph API. I can get it in JSON at the moment, but I'm 开发者_StackOverflow中文版not sure how to check and see if the ID is in it.

Here's the link to the JSON

I think you're going to have to use FQL. Using FQL you can query the group_member table:

SELECT * FROM group_member WHERE uid = USER_ID AND gid = GROUP_ID