private void AvailableBtn_Click(object sender, EventArgs e)
        {
            this.Hide();
            AvailableForT UG = new AvailableForT(uid);

            UG.Show();
        }
        private void SubmitBtn_Click(object sender, EventArgs e)
        {
            con = new SqlConnection(@"data source= rafi\SqlExpress;" +
                                    "database= Course;" +
                                    "integrated security= SSPI");
            con.Open();
            int a = 0;

            if (checkBox1.Checked)
            {
                cmd = new SqlCommand("Insert into preference(pretid, precid) values (@name, @gen)", con);
                cmd.Parameters.AddWithValue("@name", i);
                cmd.Parameters.AddWithValue("@gen", "CSE101");
                cmd.ExecuteNonQuery();
                a = 1;
            }

            if (checkBox2.Checked)
            {
                cmd = new SqlCommand("Insert into preference(pretid, precid) values (@name, @gen)", con);
                cmd.Parameters.AddWithValue("@name", i);
                cmd.Parameters.AddWithValue("@gen", "CSE102");
                cmd.ExecuteNonQuery();
                a = 1;
            }
            if (checkBox2.Checked)
            {
                cmd = new SqlCommand("Insert into preference(pretid, precid) values (@name, @gen)", con);
                cmd.Parameters.AddWithValue("@name", i);
                cmd.Parameters.AddWithValue("@gen", "CSE103");
                cmd.ExecuteNonQuery();
                a = 1;
            }
            if (a == 1)
            {
                MessageBox.Show("Submitted!");
                this.Hide();
                AvailableForT add = new AvailableForT(id);
                add.Show();
            }
        }