private void button4_Click(object sender, EventArgs e)
{
conn.Open();
string query = "insert into add_customer(customer_name,customer_email,customer_mobile,customer_address) values ('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "','" + textBox4.Text + "')";
MySqlDataAdapter sda = new MySqlDataAdapter(query, conn);
sda.SelectCommand.ExecuteNonQuery();
conn.Close();
MessageBox.Show("Type successfully added");
Form10 s = new Form10();
s.Show();
this.Hide();
}