using System;

using System.Windows;

using TwitchLib;

namespace WpfApplication1

{

    public partial class MainWindow : Window

    {

        //I am initializing this here so that 'client' is accessible in all member class functions.

        TwitchClient client;

        public MainWindow()

        {

            InitializeComponent();

            //This is just a basic debugging sanity check to make sure that the XAML is even functioning.

            richTextBox.Dispatcher.Invoke(new Action(() => richTextBox.AppendText("The program is running\n")));

            richTextBox.Dispatcher.Invoke(new Action(() => richTextBox.ScrollToEnd()));

        }

        private void globalChatMessageReceived(object sender, TwitchClient.OnMessageReceivedArgs e)

        {

            richTextBox.Dispatcher.Invoke(new Action(() => richTextBox.AppendText(String.Format("#{0} {1}[isSub: {2}]: {3}", e.ChatMessage.Channel, e.ChatMessage.DisplayName, e.ChatMessage.Subscriber, e.ChatMessage.Message) + "\n")));

            richTextBox.Dispatcher.Invoke(new Action(() => richTextBox.ScrollToEnd()));

        }

        private void button_Click(object sender, RoutedEventArgs e)

        {

            //I am overriding this here because I want a clean client every time the 'connect' button is pressed, so that each event wont be handled duplicate times upon disonnect/reconnect.

            TwitchClient client = new TwitchClient(new ConnectionCredentials("username", "password"), "channel");

            client.SetLoggingStatus(true);

            client.OnMessageReceived += new EventHandler<TwitchClient.OnMessageReceivedArgs>(globalChatMessageReceived);

            client.Connect();

        }

        private void button1_Click(object sender, RoutedEventArgs e)

        {

            //When this button is clicked or any member function calls client, this exception is thrown: "Object reference not set to an instance of an object."

            client.Disconnect();

        }

    }

}

​