protected void btnRegister_OnClick(object sender, EventArgs e)
    {
        
        if (Page.IsValid) {
            OdbcConnection objConn = new OdbcConnection(connectionString);
           string strSQL2 = null;
           string strRole = "Utente";
           string strSQL1 = null;
         
                strSQL1 = "SELECT * FROM Users ";
                OdbcCommand command = new OdbcCommand(strSQL1, objConn);

                // Execute the DataReader and access the data.
                OdbcDataReader reader = command.ExecuteReader();
                while (reader.Read())
                {
                    //Console.WriteLine("CustomerID={0}", reader[0]);
                    txtUsername.Text = "" + reader["username"] + "";
                }
                // Call Close when done reading.
                reader.Close();


                strSQL2 = "INSERT INTO Users (Fullname, Email, Username,Password,role,Info)";
                strSQL2 = strSQL2 + " VALUES ";
                strSQL2 = strSQL2 + "('" + txtFullname.Text + "', '" + txtEmail.Text + "', '" + txtUsername.Text + "', '" + txtPassword.Text + "','" + strRole + "','" + txtInfo.Text + "')";

                objConn.Open();

                OdbcCommand addUser = new OdbcCommand(strSQL2, objConn);
                addUser.ExecuteNonQuery();
                objConn.Close();
                Response.Redirect("login.aspx");

                objConn.Close();
   
        }
    }