Invocation of constructor on type MainWindow threw an exception

Question

I am getting this exception when running my program on other peoples computers.

The invocation of the constructor on type TCPp2pTutorialWPF.MainWindow that matches the specified binding constraints threw an exception. Coming from the PresentationFramework, method: Void RewrapException(System.Exception, System.Xaml.IXamlLineInfo, System.Uri)

the inner exception is Object reference not set to an instance of an object coming from Finalize()

I cannot reproduce this on my own system, or on a virtual machine, or figure out what's causing it. I am confused because I haven't written Finalize()

C# code:

namespace TCPp2pTutorialWPF
{
/// 
/// Interaction logic for MainWindow.xaml
/// 
public partial class MainWindow : Window
    {
    p2pchat network = null;
    SelectUsername name = new SelectUsername ();


    public void MessageRecieved(string username, string message, bool isDisconnect)
        {
        ChatText.Dispatcher.Invoke((Action) ( () =>
            {
            ChatText.AppendText(username + ": " + message+"\r");


            try
                {
                if (isDisconnect)
                    {
                    Users.Dispatcher.Invoke((Action) ( () =>
                        {
                            Users.Items.Remove(username);
                        } ));

                    }
                }
            catch (NullReferenceException f)
                {
                MessageRecieved("ERROR", "We tried accessing the name list when it was null or something (??) "+f.Message + " " + f.Source, false);
                }
            } ));



        }


    public void NewUser(string user)
        {
        ChatText.Dispatcher.Invoke(new Action(() =>
            {
            Users.Items.Add(user);
            } ));
        }


    public MainWindow()
        {

        try
            {
            InitializeComponent();
            }
        catch (Exception e)
            {
            MessageBox.Show("Error initializing main chat window " + e.Message + " " + e.Source + " " + e.HelpLink.ToString() + " " + e.TargetSite);
            }

        if (string.IsNullOrEmpty(name.UserName))
            try
                {
                name.ShowDialog();
                }
            catch (Exception e)
                {
                MessageRecieved("ERROR", e.Message, false);
                }
        network = new p2pchat();
        ChatText.AppendText("port " + network.Port + " may need to be forwarded to accept incoming connections\r");

        //add the handlers
        network.ReceivedMessageHandler += MessageRecieved;
        network.NewUserHandler += NewUser;
        network.MyUserName = name.UserName;
        network.Start();

        }



    private void ListBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {

        }



    private void Button_Click(object sender, RoutedEventArgs e)
        {
        Window1 getip = new Window1();
        try
            {
            getip.ShowDialog();
            }
        catch (Exception ee)
            {
            MessageRecieved("ERROR", ee.Message, false);
            }

        string Ip = getip.Ip;

        if (!string.IsNullOrEmpty(Ip))
            network.MakeConnection(Ip);
        }




    private void SendBox_KeyDown(object sender, KeyEventArgs e)
        {
        if (e.Key.Equals(Key.Enter))
            {
            network.SendMessage(new TextRange(SendBox.Document.ContentStart, SendBox.Document.ContentEnd).Text);
            SendBox.Document.Blocks.Clear();
            }
        }


    }
}

XAML:

EDIT: adding in screenshots of the stack traces, not going to type that. Will log it to a file for now on.

And adding in the upnp_helper code since it seems to reference it.

namespace TCPp2pTutorialWPF
{
class UPNP_Helper
    {
    UPnPNAT NatMgr;
    List ports = new List();

    public UPNP_Helper()
        {
        NatMgr = new UPnPNAT();
        }


    ~UPNP_Helper()
        {
        foreach (int i in ports)
            {
            try
                {
                NatMgr.StaticPortMappingCollection.Remove(i, "TCP");
                }
            catch
                {
                }
            }
        }





    public bool AddMappingToThisLocalIp(int port)
        {
        try
            {
            NatMgr.StaticPortMappingCollection.Add(port, "TCP", port, LocalIPAddress().ToString(), true, "p2pChat");
            ports.Add(port);
            return true;
            }
        catch
            {
            return false;
            }
        }




    private IPAddress LocalIPAddress()
        {
        if (!System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable())
            {
            return null;
            }

        IPHostEntry host = Dns.GetHostEntry(Dns.GetHostName());
        return host
            .AddressList
            .FirstOrDefault(ip => ip.AddressFamily == AddressFamily.InterNetwork);
        }

    }
}

fotg · Accepted Answer

WPF included in .NET 4.5 for windows 8.1 seems to be a slightly newer version than whats included in .NET 4.5 for windows 7, my test subjects claimed to have the latest version, but couldn't find the actual version installed. This problem was caused by app.Run(); and was solved by targeting an earlier version of .NET.

Invocation of constructor on type MainWindow threw an exception

Answers (2)

Related Questions