Question

我正在尝试将数据从串行写入USB设备到文本字段，但它一直在抛出：

调用线程无法访问此对象，因为另一个线程拥有它

我知道我必须做一些调度或类似的事情，但不确定我们是否要开始。我确信它很简单，但我画的是空白。这是我的代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.IO.Ports;
using System.Windows.Threading;

namespace serial_app_one
{
    public partial class MainWindow : Window
    {
        private SerialPortProgram _serial;

        public MainWindow()
        {
            InitializeComponent();
            _serial = new SerialPortProgram(this);
        }
    }

    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    class SerialPortProgram
    {
        // Create the serial port
        private SerialPort port;
        MainWindow _window;

        public SerialPortProgram(MainWindow window)
        {
            _window = window;
           AppendText("Incoming Data:");
            port = new SerialPort("COM3", 9600, Parity.None, 8, StopBits.One);
            // 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();    
        }      

        private void AppendText(string text)
        {                               
            _window.Dev_output.Text += string.Format("{0}{1}", text, Environment.NewLine);
        }

        private void port_DataReceived(object sender,
          SerialDataReceivedEventArgs e)
        {
            // Show all the incoming data in the port's buffer
            AppendText(port.ReadExisting());
        }
    }
}

Answer 1

试试这个..

private void AppendText(string text)
{
     Application.Current.Dispatcher.Invoke((Action)(() =>
     {
        _window.Dev_output.Text += string.Format("{0}{1}", text, Environment.NewLine);
     }));
}

Answer 2

在你的serialport类中，你需要存储UI线程的调度程序，它在构造函数中很方便。因此，将其存储起来，然后每次附加文本时都需要在该调度程序上调用

class SerialPortProgram
    {
        // Create the serial port
        private SerialPort port;
        MainWindow _window;
        private Dispatcher _dispatcher;

        public SerialPortProgram(MainWindow window)
        {
            _window = window;
            AppendText("Incoming Data:");
            port = new SerialPort("COM3", 9600, Parity.None, 8, StopBits.One);
            // Attach a method to be called when there
            // is data waiting in the port's buffer
            port.DataReceived += port_DataReceived;
            _dispatcher = Dispatcher.CurrentDispatcher;
            // Begin communications
            port.Open();

        }



        private void AppendText(string text)
        {
            _dispatcher.Invoke(() => {
               _window.Dev_output.Text += string.Format("{0}{1}", text, Environment.NewLine);
            });
        }

        private void port_DataReceived(object sender,
          SerialDataReceivedEventArgs e)
        {
            // Show all the incoming data in the port's buffer
            AppendText(port.ReadExisting());
        }
    }

抛出“调用线程无法访问此对象，因为另一个线程拥有它。”

2 个答案: