(#) custom control click event Unable to castr

 using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace prova_custom_control
{
    public partial class controllo_nuovo : UserControl
    {
        public controllo_nuovo()
        {
            InitializeComponent();
        }

        private void controllo_nuovo_Load(object sender, EventArgs e)
        {

        }
    }
}

 using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace prova_custom_control
{
    public partial class Form1 : Form
    {
        controllo_nuovo controllo = new controllo_nuovo();
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.Controls.Add(controllo);
            controllo.button1  .Click += new EventHandler(this.controllo_Click);

        }

        public void controllo_Click(System.Object sender, EventArgs e) {

            controllo_nuovo clickato = (controllo_nuovo)sender;
            this.BackColor = Color.Red;


        
        
        }


    }
}
 

891x351 31Kb

 public string testo
        {
            get { return button1.Text; }
            set { button1.Text = value; }

        }

 private void Form1_Load(object sender, EventArgs e)
        {
            bott.Click +=new EventHandler(this.bott_Click);
            bott.button1 .Click +=new EventHandler(this.bott_Click);
            this.Controls.Add(bott);

        }

        public void bott_Click(object sender, EventArgs e)
        {

            bottone_prova bott_se = sender as bottone_prova;

            this.Text = bott_se.testo;