Parse JSON to object

gistfile1.txt

NSDictionary *json = [NSJSONSerialization JSONObjectWithData:responseObject options:0 error:&error];//response object is your response from server as NSData

if ([json isKindOfClass:[NSDictionary class]]){ //Added instrospection as suggested in comment.
    NSArray *yourStaffDictionaryArray = json[@"directory"];
    if ([yourStaffDictionaryArray isKindOfClass:[NSArray class]]){//Added instrospection as suggested in comment.
        for (NSDictionary *dictionary in yourStaffDictionaryArray) {
            Staff *staff = [[Staff alloc] init];
            staff.id = [[dictionary objectForKey:@"id"] integerValue];
            staff.fname = [dictionary objectForKey:@"fName"];
            staff.lname = [dictionary objectForKey:@"lName"]; 
            //Do this for all property
            [yourArray addObject:staff];
        }
    }
}