ThreadAbortException as soon as breakpoint reached in thread

[Guest]

When setting a breakpoint in a thread that I have created and the debugger
reaches that point, Visual Studio just hangs for about 10 seconds and then,
when I try F10 the thread ends and the debug output shows a
ThreadAbortException. I'm not doing any other operation than .Start() on the
thread. What is wrong?

m_thread = new Thread(DataInThread);
m_thread.Name = "Data in thread";
m_thread.Start(new object[] { l_frm.COMport, 9600 });


public void DataInThread(object parameter)
{
//Any breakpoint in this function, irrellevant of where it is placed, stops
the execution but with a delay of about 10 seconds, and then aborts abruptly
when pressing F10

 

[Guest]

It is a Windows application, and I have heard that creating threads in
Windows applications can be difficult to get right but I don't know why. How
can I use threads so that they work together with the GUI?

 

[Jon Skeet [C# MVP]]

It is a Windows application, and I have heard that creating threads in
Windows applications can be difficult to get right but I don't know why. How
can I use threads so that they work together with the GUI?

See http://www.pobox.com/~skeet/csharp/threads/winforms.shtml

If you could post a short but complete program which demonstrates the
problem you're having, that would help. See
http://www.pobox.com/~skeet/csharp/complete.html for more information.

Jon

 

[Guest]

Lets say you have a GUI thread. When pressing a button the GUI thread creates
a thread which listens to a COM port. When the COM port listening thread gets
input from the COM port it wants to use this information from the COM port to
display in the GUI. Which is the best way to do this?

E g

class MyGUIclass
{
public delegate void DataInput(object sender, StringEventArgs evArgs);
public event DataInput OnDataInput;

public MyGUIclass()
{
InitializeComponent();
OnDataInput += new DataInput(DataInputHandler);
}
private void button_click(object sender, EventArgs e)
{
ThreadPool.QueueUserWorkItem(new WaitCallback(DataInThread), new
object[] { "COM1", 9600 });
}
}

protected void DataInThread(object parameter)
{
if (parameter.GetType() != typeof(object[]))
{
return;
}

object[] l_params = (object[]) parameter;
if (l_params.Length != 2)
{
return;
}

if (((object[])parameter)[0].GetType() != typeof(string))
{
return;
}
if (((object[])parameter)[1].GetType() != typeof(int))
{
return;
}

try
{
SerialPortHandler l_spHandler = new
SerialPortHandler((string) l_params[0], (int) l_params[1]);
l_spHandler.ReadTimeout = 500;

try
{
m_dataInThreadIsRunning = true;
while (m_dataInThreadIsRunning)
{
try
{
string l_str = l_spHandler.ReadLine();
//For some reason it hangs on the row below about
10
//seconds before it enters the DataInputHandler
//I suspect this has something to do with that
OnDataInput
//is a part of the GUI thread and here I'm trying to
use it
// in a sub-thread of the GUI thread. How to solve this?
OnDataInput(this, new StringEventArgs(l_str));
}
catch (TimeoutException)
{
}
catch (InvalidOperationException)
{
}
}
}
catch (IOException)
{
m_dataInThreadIsRunning = false;
}
l_spHandler.Dispose();
}
catch (UnauthorizedAccessException e)
{
m_dataInThreadIsRunning = false;
MessageBox.Show(e.Message);
}
}


protected void DataInputHandler(object sender, EventArgs evArgs)
{
/*Some code*/
}

 

[Jon Skeet [C# MVP]]

Lets say you have a GUI thread. When pressing a button the GUI thread creates
a thread which listens to a COM port. When the COM port listening thread gets
input from the COM port it wants to use this information from the COM port to
display in the GUI. Which is the best way to do this?

You'll need to use InvokeRequired/BeginInvoke/Invoke to make sure you
access the UI on the correct thread, as per the article I pointed you
at.

Jon