protected bool Proveedor(string email)
        {
            ENProvider user = new ENProvider(email);

            user.ReadProvider();
            if (user.empresa == "")
            {
                return(false);
            }
            return(true);
        }
        protected void Button_register_click(object sender, EventArgs e)
        {
            bool     duplicate = EmailExist();
            DateTime BirthDate = DateTime.ParseExact(tb_birth.Text, "yyyy-MM-dd", CultureInfo.InvariantCulture);

            ClearBoxes();
            if (check_age(BirthDate) && !duplicate)
            {
                HttpPostedFile file = pictureUpload.PostedFile;
                string         url  = "";
                //check file was submitted
                if (file != null && file.ContentLength > 0)
                {
                    string fname = Path.GetFileName(file.FileName);
                    url = Path.Combine("~/Imagenes/Users/", fname);
                    file.SaveAs(Server.MapPath(url));
                }
                else
                {
                    url = "~/Imagenes/fotoPerfil.jpg";
                }

                byte[] salt;

                new RNGCryptoServiceProvider().GetBytes(salt = new byte[16]);

                var pb = new Rfc2898DeriveBytes(tb_password.Text, salt, 1000);

                byte[] hash = pb.GetBytes(20);

                byte[] hashBytes = new byte[36];
                Array.Copy(salt, 0, hashBytes, 0, 16);
                Array.Copy(hash, 0, hashBytes, 16, 20);

                string passw = Convert.ToBase64String(hashBytes);

                //Create user with given info.
                if (tb_empresa.Text == "")
                {
                    ENUser user = new ENUser(0, tb_name.Text, passw, tb_email.Text, BirthDate, url, tb_empresa.Text, tb_delivery_address.Text);

                    if (user.CreateUser())
                    {
                        Label_Sending_Success.Visible = true;
                    }
                    else
                    {
                        Label_Sending_Error.Visible = true;
                    }
                }
                else
                {
                    ENProvider prov = new ENProvider(tb_name.Text, passw, tb_email.Text, BirthDate, url, tb_empresa.Text, tb_delivery_address.Text);

                    if (prov.CreateProvider())
                    {
                        Label_Sending_Success.Visible = true;
                    }
                    else
                    {
                        Label_Sending_Error.Visible = true;
                    }
                }
            }
            else if (duplicate)
            {
                Label_Duplicate_Error.Visible = true;
            }
        }