how to insert data in ms-sql server 2005 with asp.net drop downlist control

// make your connection in the web.config so you can use it easly and when you want to modfiey you will modified in on place
       using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["testConnectionString"].ConnectionString))
       {
           conn.Open();
           using (SqlCommand cmd = new SqlCommand("insert into dbo.cars(carID, Capicity, Luggage, Doors,Category,carname) values ('688', '5' , '9' , '8' ,  @parm , 'datsun')", conn))
           {
               //
               cmd.Parameters.AddWithValue("@parm", DropDownList2.SelectedValue);
               cmd.ExecuteNonQuery();
           }

       }

<configuration>
	<connectionstrings>
  <add name="testConnectionString" connectionstring="Data Source=.;Initial Catalog=test;Integrated Security=True">
   providerName="System.Data.SqlClient" />
 </add></connectionstrings></configuration>