public bool addLessonInfo(Lessons lessonInfo)
        {
            try
            {
                lessonInfo._id = lessonInfo.LessonID;
                var collect = this.mongoDatabase.GetCollection(LESSON_COLLECTION);

                var result = collect.Insert<Lessons>(lessonInfo);
                return true;
            }
            catch (Exception exp)
            {
                Console.WriteLine(exp.ToString());
                return false;

            }
        }
        public bool updateLessonInfo(Lessons lessonInfo)
        {
            try
            {
                var collect = this.mongoDatabase.GetCollection(LESSON_COLLECTION);

                var query = new QueryDocument { { "LessonID", lessonInfo.LessonID } };
                var update = new UpdateDocument {
                { "$set", new QueryDocument {
                { "LessonGroup", lessonInfo.LessonGroup},
                { "LessonName", lessonInfo.LessonName},
                { "Author", lessonInfo.Author},
                { "LessonURL", lessonInfo.LessonURL},
                { "ScriptURL", lessonInfo.ScriptURL},
                { "LessonForder", lessonInfo.LessonForder},
                { "ServerUrl", lessonInfo.ServerUrl},
                { "Status", lessonInfo.Status},
                { "Description", lessonInfo.Description},
                { "VideoURL", lessonInfo.VideoURL}
                } } };

                    var result = collect.Update(query, update);
                    var Affected = result.DocumentsAffected.ToString();
                    if (Affected != "0")
                    {
                        return true;

                    }
                    else
                    {
                        return false;
                    }

            }
            catch (Exception exp)
            {
                Console.WriteLine(exp.ToString());
                return false;

            }
        }
        public bool changeLessonStatus(Lessons lessonInfo)
        {
            try
            {
                var collect = this.mongoDatabase.GetCollection(LESSON_COLLECTION);

                var query = new QueryDocument { { "LessonID", lessonInfo.LessonID } };
                var update = new UpdateDocument {
                { "$set", new QueryDocument {
                { "Status", lessonInfo.Status}
                } } };

                    var result = collect.Update(query, update);
                    var Affected = result.DocumentsAffected.ToString();
                    if (Affected != "0")
                    {
                        return true;

                    }
                    else
                    {
                        return false;
                    }

            }
            catch (Exception exp)
            {
                Console.WriteLine(exp.ToString());
                return false;

            }
        }