我需要使用从串口接收的字符串更新Windows窗体标签。我的代码已经存在两个问题。
因为读取串口需要另一个线程,所以我使用委托方法来更新标签文本。
第一个问题是表单窗口在我启动程序时不会打开(当我在initSerialPort()
中没有调用Form1_Load()
时它会打开。)
第二个问题是,当我在Debug.Write(message)
中呼叫_self.SetText(message)
时似乎无法触及Read()
。当我注释掉_self.SetText(message)
时,它会记录消息,但也不会打开表单窗口,因为在initSerialPort()
中调用了Form1_Load()
我有点像C#的菜鸟,只是你知道;)
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO.Ports;
using System.Threading;
using System.Diagnostics;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
delegate void SetTextCallback(string text);
private static SerialPort _serialPort;
private static Boolean _continue;
private static StringComparer stringComparer = StringComparer.OrdinalIgnoreCase;
private static Thread readThread = new Thread(Read);
private static Form1 _self;
private static Label _lbl;
public Form1()
{
InitializeComponent();
_self = this;
_lbl = label1;
}
private void Form1_Load(object sender, EventArgs e)
{
initSerialPort();
}
public void setMessage(string mes)
{
label1.Text = mes;
}
private static void initSerialPort()
{
// Create a new SerialPort object with default settings.
_serialPort = new SerialPort("COM3", 9600, Parity.None, 8, StopBits.One);
// Set the read/write timeouts
_serialPort.ReadTimeout = 500;
_serialPort.WriteTimeout = 500;
_serialPort.Open();
_continue = true;
readThread.Start();
readThread.Join();
_serialPort.Close();
_serialPort = null;
}
public static void Read()
{
Debug.Write("testread");
while (_continue)
{
try
{
String message = _serialPort.ReadLine();
_self.SetText(message);
Debug.Write(message);
}
catch (TimeoutException) { }
}
}
private void SetText(string text)
{
// InvokeRequired required compares the thread ID of the
// calling thread to the thread ID of the creating thread.
// If these threads are different, it returns true.
if (this.label1.InvokeRequired)
{
SetTextCallback d = new SetTextCallback(SetText);
this.Invoke(d, new object[] { text });
}
else
{
this.label1.Text = text;
}
}
}
}
答案 0 :(得分:0)
不要Join
到您创建的新主题。这将阻止线程,直到您的Read
方法完成,这意味着它永远不会完成。