Check if the current user belongs a specific Windows group/role

From CodeCodex



You can connect to the ActiveDirectory or use some API but an easy way is to use a connection to SQL Server. Send the query :

SELECT is_member('mydomain\g_dept')

and the result can be

0     Current user is not a member of group or role. 

1     Current user is a member of group or role. 

NULL  Either group or role is not valid.