Active directory check if user belongs to a group

Question

I am using the below code to pull active directory groups. How can I find out if a user belongs to xyz group or not?

// create your domain context
PrincipalContext ctx = new PrincipalContext(ContextType.Domain);

// define a "query-by-example" principal - here, we search for a GroupPrincipal 
GroupPrincipal qbeGroup = new GroupPrincipal(ctx);

// create your principal searcher passing in the QBE principal    
PrincipalSearcher srch = new PrincipalSearcher(qbeGroup);

// find all matches
foreach(var found in srch.FindAll())
{
    // do whatever here - "found" is of type "Principal" - it could be user, group, computer.....          
}

Answer 1

You can get the list of groups a user is a member of by querying the memberOf navigation property on the user object.

Read about it here.

https://graph.windows.net/myorganization/users/{user_id}/$links/memberOf?api-version

Note that you can remove the $links part of the query to return the whole group object, rather than the link to the object. However, for simply validating a user is a member of a certain group, you can use the links, and compare the object id of the groups that are returned to the one you are looking for.