http://blogs.msdn.com/bclteam/archive/2006/10/10/Top-5-SerialPort-Tips-_5B00_Kim-Hamilton_5D00_.aspx
Tip 3. Take care to avoid deadlock when calling Close
on the SerialPort in response to a GUI event.
- An app involving the UI and the SerialPort freezes up when closing the SerialPort
- Deadlock can occur if
Control.Invoke()
is used in serial port event handlers
This is probably the most frustrating SerialPort issue because it may happen so rarely that it’s hard to diagnose. Deadlocks can happen if you have an event handler trying to work with a GUI control while the GUI thread is trying to close the SerialPort. This happens in the following example.
public partial class Form1 : Form
{
SerialPort m_port;
public Form1()
{
InitializeComponent();
m_port = new SerialPort("COM2", 115200);
m_port.DataReceived += new
SerialDataReceivedEventHandler(m_port_DataReceived);
m_port.Open();
}
void m_port_DataReceived(object sender,
SerialDataReceivedEventArgs e)
{
this.Invoke(new EventHandler(delegate
{
m_port.Close();
}));
}
}
This example looks a bit strange, but it forces the deadlock to occur. The typical scenario we encounter is occasional deadlock in an app that has a data received handler trying to update the GUI at the same time the GUI thread is trying to close the SerialPort (for example, in response to the user clicking a Close button).
The reason deadlock happens is that Close
() waits for events to finish executing before it closes the port. You can address this problem in your apps in two ways:
- In your event handlers, replace every
Control.Invoke
call withControl.BeginInvoke
, which executes asynchronously and avoids the deadlock condition. This is commonly used for deadlock avoidance when working with GUIs. - Call
serialPort.Close
() on a separate thread. You may prefer this because this is less invasive than updating yourInvoke
calls.
【推荐】编程新体验,更懂你的AI,立即体验豆包MarsCode编程助手
【推荐】凌霞软件回馈社区,博客园 & 1Panel & Halo 联合会员上线
【推荐】抖音旗下AI助手豆包,你的智能百科全书,全免费不限次数
【推荐】博客园社区专享云产品让利特惠,阿里云新客6.5折上折
【推荐】轻量又高性能的 SSH 工具 IShell:AI 加持,快人一步
· DeepSeek 解答了困扰我五年的技术问题
· 为什么说在企业级应用开发中,后端往往是效率杀手?
· 用 C# 插值字符串处理器写一个 sscanf
· Java 中堆内存和栈内存上的数据分布和特点
· 开发中对象命名的一点思考
· DeepSeek 解答了困扰我五年的技术问题。时代确实变了!
· PPT革命!DeepSeek+Kimi=N小时工作5分钟完成?
· What?废柴, 还在本地部署DeepSeek吗?Are you kidding?
· 赶AI大潮:在VSCode中使用DeepSeek及近百种模型的极简方法
· DeepSeek企业级部署实战指南:从服务器选型到Dify私有化落地