/// <summary>
        ///
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="context"></param>
        /// <param name="entities"></param>
        /// <param name="sqlBulkCopyOptions"></param>
        /// <param name="batchSize"></param>
        public static void BulkInsert <T>(this DbContext context, IEnumerable <T> entities, SqlBulkCopyOptions sqlBulkCopyOptions, int?batchSize = null)
        {
            var options = new BulkInsertOptions {
                SqlBulkCopyOptions = sqlBulkCopyOptions
            };

            if (batchSize.HasValue)
            {
                options.BatchSize = batchSize.Value;
            }
            context.BulkInsert(entities, options);
        }
 /// <summary>
 ///
 /// </summary>
 /// <typeparam name="T"></typeparam>
 /// <param name="context"></param>
 /// <param name="entities"></param>
 /// <param name="batchSize"></param>
 public static void BulkInsert <T>(this DbContext context, IEnumerable <T> entities, int?batchSize = null)
 {
     context.BulkInsert(entities, SqlBulkCopyOptions.Default, batchSize);
 }