gistfile1.cs

    public class BulkWriteResult
    {
        public bool IsOrdered { get; }
        public int DocumentsAffectedCount { get; }
        public IList<WriteRequest> ProcessedRequests { get; }
        public IList<BulkWriteUpsert> Upserts { get; }
    }

    public class BulkWriteException : Exception
    {
        public BulkWriteResult Result { get; }
        public IList<BulkWriterError> Errors { get; }
        public IList<WriteRequest> UnprocessedRequests { get; }
    }

    public class BulkWriteError
    {
        public int ErrorCode { get; }
        public BsonDocument ErrorInfo { get; }
        public string ErrorMessage { get; }
        public IList<int> Indexes { get; } // the same error can apply to multiple items
    }

    public class BulkWriteUpsert
    {
        public BsonValue Id { get; }
        public int Index { get; }
    }