This is an odd issue. When working on this yesterday, the program would stop, highlight the area of code I was working on and present "NullReferenceException," and linked to this page.
NullReferenceException Class
TODAY, without changes I am getting the error in the title.
I am learning c#, and found an application in an area I have need to learn.
After coming along fine, and using this example on learning more, I ran into issues with limitations in Windows Forms, thus started the change to WPF.
The original code I am working with can be found here:
Paste Bine: PCCom.SerialCommunication Version 1.0.0.0
You can download the entire original project, if you wish, at
www.dreamincode.net - Serial Cmmunications Project
Here is the section of code presenting the error. The error occurs when "return true;" is executed.
#region OpenPort
public bool OpenPort()
{
try
{
//first check if the port is already open
//if its open then close it
if (comPort.IsOpen == true) comPort.Close();
//set the properties of our SerialPort Object
comPort.BaudRate = int.Parse(_baudRate); //BaudRate
comPort.DataBits = int.Parse(_dataBits); //DataBits
comPort.StopBits = (StopBits)Enum.Parse(typeof(StopBits), _stopBits); //StopBits
comPort.Parity = (Parity)Enum.Parse(typeof(Parity), _parity); //Parity
comPort.PortName = _portName; //PortName
//now open the port
comPort.Open();
return true;
}
catch (Exception ex)
{
DisplayData(ex.Message);
return false;
}
}
#endregion
I have no idea on what is going on with this. Some helpful explanations would be great.
The error I was having yesterday, was in another section of the program:
What I am currently working on is:
private RichTextBox _displayWindow;
I have since changed to:
private TextBox _displayWindow;
And the code I have been working on to convert to wpf which generated the NullReferenceException
private void DisplayData(string msg)
{
_displayWindow.Dispatcher.Invoke(new EventHandler(delegate
{
_displayWindow.SelectedText = string.Empty;
_displayWindow.AppendText(msg);
_displayStatus.ScrollToLine(_displayStatus.GetLineIndexFromCharacterIndex(_displayStatus.SelectionStart));
//_displayWindow.ScrollToCaret();
}));
}
Thanks