事件处理程序&；代表(简单问题)

我有一个简单的应用程序。以下是它的工作原理。我有一个从Windows继承的类（MyForm）。表格。它有一个按钮、一个标签和一个文本框。它看起来像一个聊天窗口。还有另一个类（Cliente），它接受一个字符串数组，并为数组中的每个元素返回一个带有MyForm实例的List。

我有第三个类（Prueba），它利用前两个类来测试它们。这个类创建MyForm的四个实例，并显示它们。（我将省略一些代码和功能，因为我知道它工作正常。）

我需要能够在一个窗口中键入一些内容，当单击按钮时，它应该会广播此消息并在所有其他窗口中显示。我知道我必须使用事件处理程序和委托，但在到处看了几个小时的教程后，我不知道该把什么放在哪里。

你能帮帮我吗？如果你能给我指一个好的教程或例子就足够了，但如果你能更具体地了解我的代码，那就太好了。

（我不知道如何让MyForm的一个实例意识到其他实例，谁应该是这里的监听器？我在想客户端，但我不知道该怎么做。）任何帮助都将不胜感激！

    //MyForm
    namespace Dia26 {
        //public delegate void ChangedEventHandler(object sender, EventArgs e);
        public class MyForm : System.Windows.Forms.Form {
            public Button btn = new Button();
            public TextBox textbox = new TextBox();
            public Label label = new Label();
            public Button btnEnviar = new Button();
            public delegate void OwnerChangedEventHandler(string newOwner); //~
            public event OwnerChangedEventHandler OwnerChanged;
            protected void btn_Click(object sender, System.EventArgs e) {
                this.Close();
            }
            protected void btnEnviar_Click(object sender, System.EventArgs e) {
                label.Text += textbox.Text + "'n";
                textbox.Text = "";
                if (this.OwnerChanged != null) {
                    this.OwnerChanged("something?");
                }
            }
            public MyForm() {
                btn.Text = "cerrar";
                btn.Left = 400;
                btn.Top = 280;
                btn.Click += new EventHandler(this.btn_Click);
                btnEnviar.Click += new EventHandler(this.btnEnviar_Click);
                textbox.Left = 15;
                textbox.Top = 20;
                textbox.Width = 330;
                label.Left = 15;
                label.Top = 50;
                label.AutoSize = false;
                label.Height = 210;
                label.Width = 450;
                label.BackColor = Color.White;
                btnEnviar.Left = 350;
                btnEnviar.Top = 17;
                btnEnviar.Text = "Enviar";
                this.Controls.Add(textbox);
                this.Controls.Add(label);
                this.Controls.Add(btn);
                this.Controls.Add(btnEnviar);
                this.SuspendLayout();
                this.Name = "MyForm";
                this.ResumeLayout(false);
                return;
            }
        }
    }

    //Cliente.cs
 namespace Dia26Prueba {
    public class Cliente {
        public int creadas;
        public int nocreadas;
        public List<MyForm> MostrarVentanas(out bool error, ref int creadas, params string[] nombres) {
            List<MyForm> list = new List<MyForm>();
            int bienCreadas = 0;
            foreach (string str in nombres) {
                if (str.Length >= 1) {
                    MyForm mf = new MyForm();
                    mf.Text = str;
                    //mf.OwnerChanged += new OwnerChangedEventHandler(mf_OwnerChanged);
                    list.Add(mf);
                    mf.Show();
                    bienCreadas++;
                }
            }
            error = (bienCreadas == creadas);
            nocreadas = bienCreadas - creadas;
            creadas = bienCreadas;
            return list;
        }
        public void ModificarPosicionYMedidas(MyForm mf, int x = 262, int y = 209, int width = 500, int height = 350) {
            mf.Left = x;
            mf.Top = y;
            mf.Width = width;
            mf.Height = height;
        }
    }
}
// Prueba
namespace Dia29 {
    class Prueba {
        static void Main(string[] args) {
            Cliente cliente = new Cliente();
            int n = 4;
            Console.WriteLine(cliente.Autor);
            if (args.Length != n) {
                return;
            }
            int InstanciasCreadas = n;
            bool HayErrores;
            List<Dia26.MyForm> list;
            list = cliente.MostrarVentanas(
               creadas: ref InstanciasCreadas,
               error: out HayErrores,
               nombres: new string[] { "FirstWindow", "2nd", "3rd", "4th" });
            cliente.ModificarPosicionYMedidas(list.ElementAt<MyForm>(0), 0, 0, 512, 384);
            cliente.ModificarPosicionYMedidas(list.ElementAt<MyForm>(1), 512, 0, 512, 384);
            cliente.ModificarPosicionYMedidas(list.ElementAt<MyForm>(2), 0, 384, 512, 384);
            cliente.ModificarPosicionYMedidas(list.ElementAt<MyForm>(3), 512, 384, 512, 384);
            for (int i = 0; i < n; i++) {
                // .....
                Application.Run(list.ElementAt<MyForm>(i));
            }           

            Console.ReadLine();
        }
    }
}

public class ChatEventArgs : EventArgs
{
    public string ChatEventArgs(string message)
    {
        Message = message;
    }
    public string Message { get; private set; }
}

public interface IChatMessageProvider
{
    event EventHandler<ChatEventArgs> MessageArrived;
    void TriggerEvent(object source, ChatEventArgs args);
}
public class MainWindow : IChatMessageProvider
{
    public event EventHandler<ChatEventArgs> MessageArrived = delegate{};
    public void AddChatWindow()
    {
        ChatWindow window = new ChatWindow(this);
        window.Show();
    }
    public void TriggerEvent(object source, ChatEventArgs args)
    {
        MessageArrived(source, args);
    }
}
public class ChatWindow : 
{
    IChatMessageProvider _provider;
    public ChatWindow(IChatMessageProvider provider)
    {
        _provider = provider;
        provider.MessageArrived += OnMessage;
    }

    public void OnMesage(object source, ChatEventArgs args)
    {
        // since we could have sent the message
        if (source == this)
            return;
        myListBox.Items.Add(args.Message);
    }
    public void SendButton_Click(object source, EventArgs e)
    {
        _provider.TriggerEvent(this, new ChatEventArgs(Textbox1.Text));
    }
}