/// <summary>
 /// Add pagination cursor.
 /// </summary>
 public void AddCursor(FbCursor fbCursor)
 {
     if (fbCursor != null)
     {
         AddCommand(fbCursor.Type.ToString(), fbCursor.Value);
     }
 }
        /// <summary>
        /// This edge allows you to:
        /// get the User's friends who have installed the app making the query
        /// get the User's total number of friends (including those who have not installed the app making the query)
        /// <para>Requires  <b>"user_friends" </b> permission
        /// <see href="https://developers.facebook.com/docs/graph-api/reference/user/friends"/> for information </para>
        /// </summary>
        /// <param name="limit">Result limit </param>
        /// <param name="callback">Request callback </param>
        /// <param name="fbCursor">Pagination cursor pointer </param>
        public void GetFriends(int limit, Action <FbGraphFriendsListResult> callback, FbCursor fbCursor = null)
        {
            var request = new FbRequestBuilder("/me?fields=friends");

            request.AddLimit(limit);
            request.AddCommand("fields", "first_name,id,last_name,name,link,locale,picture");
            request.AddCursor(fbCursor);

            Fb.API(request.RequestString, HttpMethod.GET,
                   graphResult =>
            {
                var result = new FbGraphFriendsListResult(graphResult);
                callback.Invoke(result);
            });
        }
 /// <summary>
 /// This edge allows you to:
 /// get the User's friends who have installed the app making the query
 /// get the User's total number of friends (including those who have not installed the app making the query)
 /// <para>Requires  <b>"user_friends" </b> permission
 /// <see href="https://developers.facebook.com/docs/graph-api/reference/user/friends"/> for information </para>
 /// </summary>
 /// <param name="limit">Result limit </param>
 /// <param name="callback">Request callback </param>
 /// <param name="fbCursor">Pagination cursor pointer </param>
 public static void GetFriends(int limit, Action <FbGraphFriendsListResult> callback, FbCursor cursor)
 {
     FbGraphApi.GetFriends(limit, callback, cursor);
 }