使用 .NET 框架读取串行端口的正确方法是什么？

Question

我在这里阅读了很多关于如何使用 .NET SerialPort 类从串行端口读取数据的问题，但没有一种推荐的方法对我来说完全有效。

这是我现在使用的代码：

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

以及事件处理程序：

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

但有时我仍然会丢失一些数据。我尝试了不同的方式来读取事件处理程序中的数据，但没有成功。

由于 .NET 4.5 为执行一些异步任务带来了新的可能性，例如似乎可以在 SerialPort 流上使用的 ReadAsync 方法，我很想知道处理这些情况的推荐方法是什么.

Answer 1

您可以尝试这样的事情吗？例如，我认为您想要使用的是 port.ReadExisting() 方法

 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()); 
    } 
}

或者你想根据你想做的事情来做，你可以试试这个

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();
        }
  }

Answer 2

我使用了与@MethodMan 类似的代码，但我必须跟踪串行端口正在发送的数据并查找终止字符以了解串行端口何时完成发送数据。

private string buffer { get; set; }
private SerialPort _port { get; set; }

public Port() 
{
    _port = new SerialPort();
    _port.DataReceived += new SerialDataReceivedEventHandler(dataReceived);
    buffer = string.Empty;
}

private void dataReceived(object sender, SerialDataReceivedEventArgs e)
{    
    buffer += _port.ReadExisting();

    //test for termination character in buffer
    if (buffer.Contains("\r\n"))
    {
        //run code on data received from serial port
    }
}

Answer 3

    using System;
    using System.IO.Ports;
    using System.Threading;

    namespace SerialReadTest
    {
        class SerialRead
        {
            static void Main(string[] args)
            {
        Console.WriteLine("Serial read init");
        SerialPort port = new SerialPort("COM6", 115200, Parity.None, 8, StopBits.One);
        port.Open();
        while(true){
          Console.WriteLine(port.ReadLine());
        }

    }
}
}