using System;
using System.Windows;
using System.Windows.Forms;

namespace FormDemo
{
    class Program
    {
        static void Main()
        {
            MyForm MainForm = new MyForm("Main Waindow");
            MainForm.ShowDialog();
        }
    }
    class MyForm : Form 
    {
        private Button NewButton;
        private TextBox Output;
        public MyForm(string FormName)
        {
            Form NewForm = new Form();
            this.Text= FormName;
            this.Output=new TextBox();
            this.NewButton = new Button();
            this.Controls.Add(this.NewButton);
            this.Controls.Add(this.Output);
            this.NewButton.Text = "ShowHello";
            this.NewButton.Top = 20;
            this.NewButton.Click += ButtonClicked;

        }

        private void ButtonClicked(object sender, EventArgs e)
        {
            this.Output.Text = "Hello World";
        }
    }
}