private void button1_Click(object sender, EventArgs e)
        {
            if (validation() == 0)
            {
                errorProvider1.Clear();
                con.Open();
                SqlCommand cmd = con.CreateCommand();
                cmd.CommandType = CommandType.Text;
                cmd.CommandText = "insert into vehicle values('" + textBox1.Text + "','" + textBox2.Text + "','" + textBox3.Text + "','" + textBox5.Text + "','" + comboBox1.Text + "''" + textBox6.Text + "','" + textBox8.Text + "','" + textBox9.Text + "')";
                cmd.ExecuteNonQuery();
                con.Close();
                diplay_data();

                MessageBox.Show("Record Inserted Suuccesfully !");
                this.Close();
                Vehical_master vm = new Vehical_master();
                vm.Show();
            }
        }
        private void vehiclesToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Vehical_master vm = new Vehical_master();

            vm.Show();
        }