經典：
using system;
using system.data.oledb;
namespace courseeditor.logic
{
    /// <summary>
    /// summary description for db.
    /// </summary>
    public class db:system.data.oledb.oledbconnection
    {
        public db()
        {
            
            this.connectionstring="provider=msdaora;datasource=orcl_192.168.0.202;user id=test;password=";
            
            
        }
    }
}
在vs.net bulid 9150里面無法繼承system.data.sqlclient，不過在beta1里面可以對ado或者sql方式都極方便的繼承:)