LitS3.S3Service.CreateProgressCallback C# (CSharp) Method

        private Action<long> CreateProgressCallback(string bucketName, string key, long length,
            EventHandler<S3ProgressEventArgs> handler)
        {
            return handler != null
                 ? bytes => handler(this, new S3ProgressEventArgs(bucketName, key, bytes, length))
                 : (Action<long>)null;
        }