What is the correct way to read a serial port using .NET framework?

Question

I've read a lot of questions here about how to read data from serial ports using the .NET SerialPort class but none of the recommanded approaches have proven completely efficient for me.

Here is the code I am using for now:

SerialPort port = new SerialPort("COM1"); port.DataReceived += new SerialDataReceivedEventHandler(MyDataReceivedHandler); 

And the event handler:

void MyDataReceivedHandler(object sender, SerialDataReceivedEventArgs e) {     int count = port.BytesToRead;     byte[] ByteArray = new byte[count];     port.Read(ByteArray, 0, count); } 

But I am still missing some data sometimes. I've tried different way of reading the data in the event handler but with no luck.

As the .NET 4.5 brings new possibilities to do some asynchronous tasks, like with the ReadAsync method that seems to be useable on a SerialPort stream, I'm curious to see what would be the recommended approach to handle those cases.

Answer 1

Could you try something like this for example I think what you are wanting to utilize is the port.ReadExisting() Method

 using System;  using System.IO.Ports;   class SerialPortProgram   {    // Create the serial port with basic settings      private SerialPort port = new   SerialPort("COM1",       9600, Parity.None, 8, StopBits.One);      [STAThread]      static void Main(string[] args)      {        // Instatiate this        SerialPortProgram();      }       private static void SerialPortProgram()      {          Console.WriteLine("Incoming Data:");          // Attach a method to be called when there          // is data waiting in the port's buffer          port.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);          // Begin communications          port.Open();          // Enter an application loop to keep this thread alive          Console.ReadLine();      }       private void port_DataReceived(object sender, SerialDataReceivedEventArgs e)      {         // Show all the incoming data in the port's buffer        Console.WriteLine(port.ReadExisting());      }  } 

Or is you want to do it based on what you were trying to do , you can try this

public class MySerialReader : IDisposable {   private SerialPort serialPort;   private Queue<byte> recievedData = new Queue<byte>();    public MySerialReader()   {     serialPort = new SerialPort();     serialPort.Open();     serialPort.DataReceived += serialPort_DataReceived;   }    void serialPort_DataReceived(object s, SerialDataReceivedEventArgs e)   {     byte[] data = new byte[serialPort.BytesToRead];     serialPort.Read(data, 0, data.Length);     data.ToList().ForEach(b => recievedData.Enqueue(b));     processData();   }    void processData()   {     // Determine if we have a "packet" in the queue     if (recievedData.Count > 50)     {         var packet = Enumerable.Range(0, 50).Select(i => recievedData.Dequeue());     }   }    public void Dispose()   {         if (serialPort != null)         {             serialPort.Dispose();         }   }