How i can Change my date into yyyy-mm-dd format and this From and to are parameters of SQL  Stored Procedure  .so please tell me what i do
 txt_from.Text='01/08/2015';
 txt_to.Text='03/08/2015';
 
 DateTime from = new DateTime(Convert.ToInt32(txt_from.Text.Split('/')[2]), Convert.ToInt32(txt_from.Text.Split('/')[1]), Convert.ToInt32(txt_from.Text.Split('/')[0]));
       DateTime to = new DateTime(Convert.ToInt32(txt_to.Text.Split('/')[0]), Convert.ToInt32(txt_to.Text.Split('/')[1]), Convert.ToInt32(txt_to.Text.Split('/')[2]));
  if (to > Convert.ToDateTime(DateTime.Now.ToShortDateString()))
        {
            RegisterClientScriptBlock("alert", "<script>alert('To date can not be later than current date.');</script>");
        }
        else
        {
            to = to.AddDays(1);
            if (from <= to)
            {
                SqlParameter[] param = new SqlParameter[]
         {
             new SqlParameter("@from",from),
             new SqlParameter("@to",to),
             new SqlParameter("@PortalId",Convert.ToInt32( Session["PortalId"]))
         
         };