C# how to stop backgroundworker correctly?

This code below I found on the Internet. This is a simple example of code how works BackgroundWorker, and it works well.
I need the code to Abort (stop) BackgroundWorker correctly. 
I want to know how it works. Thanks a lot.

private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
        {
            byte[] buffer;
            byte[] oldBuffer;
            int bytesRead;
            int oldBytesRead;
            long size;
            long totalBytesRead = 0;
          
            using (Stream stream = File.OpenRead((string) e.Argument))
            using (HashAlgorithm hashAlgorithm = MD5.Create())
            {
                size = stream.Length;

                buffer = new byte[4096];

                bytesRead = stream.Read(buffer, 0, buffer.Length);
                totalBytesRead += bytesRead;

                do
                {
                    oldBytesRead = bytesRead;
                    oldBuffer = buffer;

                    buffer = new byte[4096];
                    bytesRead = stream.Read(buffer, 0, buffer.Length);

                    totalBytesRead += bytesRead;

                    if (bytesRead == 0)
                    {
                        hashAlgorithm.TransformFinalBlock(oldBuffer, 0, oldBytesRead);
                    }
                    else
                    {
                        hashAlgorithm.TransformBlock(oldBuffer, 0, oldBytesRead, oldBuffer, 0);
                    }

                    BackgroundWorker.ReportProgress((int)((double)totalBytesRead * 100 / size));
                } while (bytesRead != 0);

                e.Result = hashAlgorithm.Hash;
            }
        }

        private void BackgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            StringBuilder sb;

            sb = new StringBuilder();

            ProgressPercentage.Visible = false;
            ProgressBar.Visible = false;
            StatusText.Text = "";

            foreach (byte b in (byte[]) e.Result)
            {
                sb.AppendFormat("{0:X2}", b);
            }
            HashTextbox.Text = sb.ToString();
            
        }

        private void BackgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            ProgressBar.Value = e.ProgressPercentage;
            ProgressPercentage.Text = e.ProgressPercentage + "%";
        }