拒絕訪問端口“COM5”

Question

我收到以下錯誤消息Access to the port 'COM5' is denied. 從我的表單運行下面的方法時。 我嘗試從設備管理器的端口設置中輸入正確的波特率 9600。 我也嘗試通過 Portmon 訪問設備，但有一個錯誤阻止我連接。 有什么辦法可以解決這個問題嗎？

      //Fields
    List<string> myReceivedLines = new List<string>();

    //subscriber method for the port.DataReceived Event
    private void DataReceivedHandler(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
    {
        SerialPort sp = (SerialPort)sender;
        while (sp.BytesToRead > 0)
        {
            try
            {
                myReceivedLines.Add(sp.ReadLine());
            }
            catch (TimeoutException)
            {
                break;
            }
        }
    }

    protected override void SolveInstance(IGH_DataAccess DA)
    {

        string selectedportname = default(string);
        DA.GetData(1, ref selectedportname);
        int selectedbaudrate = default(int);
        DA.GetData(2, ref selectedbaudrate);
        bool connecttodevice = default(bool);
        DA.GetData(3, ref connecttodevice);

        port.DtrEnable = true;   //enables the Data Terminal Ready (DTR) signal during serial communication (Handshaking)
        port.Open();             //Open the port
        if (!(port.IsOpen == true)) port.Open();


        if (connecttodevice == true)
        {
            port.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);
            DA.SetDataList(0, myReceivedLines);
        }

Answer 1

您需要將 SerialPort 的使用包裝在using 語句中或實現IDisposable

// Dispose() calls Dispose(true)
public void Dispose()
{
    Dispose(true);
    GC.SuppressFinalize(this);
}

// The bulk of the clean-up code is implemented in Dispose(bool)
protected virtual void Dispose(bool disposing)
{
    if (disposing)
    {
        // free managed resources
        if (_serialPort != null)
        {
            _serialPort.Dispose();
            _serialPort = null;
        }
    }
    // free native resources if there are any.
}

Answer 2

我的串口監聽器有問題，主進程卡住了 - 因為它是同步的。 進程，通過創建一個線程和一個計時器來解決

                try
            {
                if (_serialConnection.IsOpen) _serialConnection.Close();
                _serialConnection.Open();
                Thread newThread = new Thread((obj) =>
                {
                    System.Timers.Timer timer = new System.Timers.Timer();
                    timer.Interval = 1000;
                    timer.Elapsed += (sender, e) =>
                    {
                        _slave.Listen();
                    };
                    timer.Enabled = true;
                    timer.Start();
                    
                });
                newThread.IsBackground = true;
                newThread.Start();
            }
            catch (Exception ex)
            {
                throw ex;
            }