SqlConnection con = new SqlConnection(constr);
            SqlCommand cmd = new SqlCommand("insert into reg (name,num,gender,qual) values (@name,@num,@gender,@qual)", con);
            cmd.Parameters.AddWithValue("@name", TextBox1.Text);
            cmd.Parameters.AddWithValue("@num", TextBox2.Text);
            cmd.Parameters.AddWithValue("@gender", RadioButtonList1.SelectedItem.ToString());

class Program
    {
        static void Main(string[] args)
        {
            string[] names = new string[] { "kasi", "rajan" };
            using (StreamWriter sw = new StreamWriter("jamica.txt")) 
            {
                foreach (string s in names)
                {
                    Console.WriteLine(s);
                }