How to While Loop Exit?

using (XmlReader reader = XmlReader.Create(new StringReader(recievedXML), xrs))
    {

        while (reader.Read())
        {
            if (reader.IsStartElement())
            {
                switch (reader.Name)
                {
                    case "start":
                        String time = DateTime.Now.TimeOfDay.ToString();
                        StartTimeTextBox.Text = time.Substring(0, time.Length-8);
                        break;
                     case "vol":

                        if (reader.Read())
                        {
                            volumeTextBox.Text = reader.Value;
                            csvData.Append(reader.Value + ";");
                        }
                        else
                        {
                            MessageBox.Show("Data Not Read");

/// ====================================> I want to whlie Loop exit here     <===============
                        }
                        String time1 = DateTime.Now.TimeOfDay.ToString();
                        EndTimeTextBox.Text = time1.Substring(0, time1.Length-8);
                        break;
                    case "hct":
                        if (reader.Read())
                        {
                            HctTextBox.Text = reader.Value;
                            csvData.Append(reader.Value + ";");
                        }
                        break;
                    case "joule":
                        if (reader.Read())
                        {
                            EnergyTextBox.Text = "00"+reader.Value;
                            csvData.Append("00"+reader.Value + ";");
                        }
                        break;
                    /*case "jouleend":
                        if (reader.Read())
                        {
                            jouleendTextBox.Text = reader.Value;
                            csvData.Append("jouleend," + reader.Value + "\n");
                        }
                        break;*/
                    case "complete":
                        if (reader.Read())
                        {
                            ProcedureCompletedTextBox.Text = "OK";
                            csvData.Append("OK" + ";");
                        }
                        break;
                    case "runtime":
                        if (reader.Read())
                        {
                            TotalTimeTextBox.Text = reader.Value;
                            csvData.Append(reader.Value + ";");
                        }
                        break;
                    case "pausetime":
                        if (reader.Read())
                        {
                            PauseTextBox.Text = reader.Value;
                            csvData.Append(reader.Value + ";");
                        }
                        break;
                    case "nrpause":
                        if (reader.Read())
                        {
                            NoOfPauseTextBox.Text = reader.Value;
                            csvData.Append(reader.Value + ";");
                        }
                        break;
                    case "temperature":
                        if (reader.Read())
                        {
                            temperatureTextBox.Text = "00"+reader.Value;
                            csvData.Append("00"+reader.Value + ";");
                        }
                        break;
                }
            }
        }
    }
}
catch (Exception e)
{
    String fileName = Path.GetPathRoot(Environment.SystemDirectory) + "\\MED_DATA\\exception_" + DateTime.Now.ToString("ddMMyyyyhhmmss") + ".txt";
    File.WriteAllText(fileName, e.Message + "\n" + e.StackTrace + "\n" + e.Source + "\n" + e.InnerException + "\n" + e.ToString());
}