private void button1_Click(object sender, EventArgs e)
    {
        string query = "SELECT * FROM usuario WHERE user=@nome AND pass=@senha";
       ;


        Conexao conexao = new Conexao();
        conexao.conectar();

       MySqlCommand cmd = new MySqlCommand(query,conexao.con);


        cmd.Parameters.AddWithValue("@nome", txtUser.Text  );
        cmd.Parameters.AddWithValue("@senha", txtSenha.Text);

        MySqlDataReader leia =  cmd.ExecuteReader();

        if (leia.Read())
        {

            btloadhack.Enabled = true;
        }
        else
        {

            MessageBox.Show("User or password incorrect!");
        }
    }