I have a winform program that performs several asynchronous I / O on SerialPort. However, I occasionally encounter a problem with freezing a program by calling SerialPort.Close (), it would seem, randomly.
I think this is a thread safety issue, but I'm not sure how to fix it, if so. I tried adding / removing an async DataReceived handler with port open / close functions and dumping input and output buffers on the port, but it does nothing. I think the important SerialPortcode is below:
using System;
using System.Collections.Generic;
using System.IO.Ports;
public class SerialComm
{
private object locker = new object();
private SerialPort port;
private List<byte> receivedBytes;
public SerialComm(string portName)
{
port = new SerialPort(portName);
port.BaudRate = 57600;
port.Parity = Parity.None;
port.DataBits = 8;
port.StopBits = StopBits.One;
receivedBytes = new List<byte>();
}
public void OpenPort()
{
if(port!=null && !port.IsOpen){
lock(locker){
receivedBytes.Clear();
}
port.DataReceived += port_DataReceived;
port.Open();
}
}
public void ClosePort()
{
if(port!=null && port.IsOpen){
port.DataReceived -= port_DataReceived;
while(!(port.BytesToRead==0 && port.BytesToWrite==0)){
port.DiscardInBuffer();
port.DiscardOutBuffer();
}
port.Close();
}
}
private void port_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
try{
byte[] buffer = new byte[port.BytesToRead];
int rcvdBytes = port.Read(buffer, 0, buffer.Length);
lock(locker){
receivedBytes.AddRange(buffer);
}
} catch (Exception ex) {
System.Diagnostics.Debug.WriteLine(ex.ToString());
}
}
}
UPDATE
@Afrin, ( ), !
private void port_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
try{
byte[] buffer = new byte[port.BytesToRead];
int rcvdBytes = port.Read(buffer, 0, buffer.Length);
lock(locker){
receivedBytes.AddRange(buffer);
}
ThreadPool.QueueUserWorkItem(handleReceivedBytes);
} catch (Exception ex) {
System.Diagnostics.Debug.WriteLine(ex.ToString());
}
}
private void handleReceivedBytes(object state)
{
}