So what is the Big deal.
Now Use insert query ob button click:
SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["Con"].ToString());
cn.Open();
string qry = "insert into Table_Name([Your_Column1],[Your_Column2])VALUES(@Your_Column1,@Your_Column2)";
SqlCommand cmd = new SqlCommand(qry,cn);
cmd.Parameters.Add("@Your_Column1", SqlDbType.YourDataType).Value = TextBOX1.Text;
cmd.Parameters.Add("@Your_Column2",SqlDbType.VarChar).Value = DropDownList1.SelectedValue;
cmd.ExecuteNonQuery();
cn.close();