// POST api/Usuario
        public void Post([FromBody] string value)
        {
            Models.User             user = JsonConvert.DeserializeObject <Models.User>(value);
            Models.ToastDataContext dc   = new Models.ToastDataContext();
            //dc.Usuarios.InsertOnSubmit(
            //    new Models.Usuario { Nome = user.Nome, Url = user.Url });
            // Verifica se usuário existe
            var listUser = from f in dc.Usuarios
                           where string.Equals(f.Nome, user.Nome)
                           select f;

            if (listUser.Count() == 0)
            {
                dc.Usuarios.InsertOnSubmit(
                    new Models.Usuario {
                    Nome = user.Nome, Uri = user.Uri
                });
            }
            else
            {
                Models.Usuario x = listUser.FirstOrDefault();
                x.Uri = user.Uri;
            }
            dc.SubmitChanges();
        }
        // DELETE api/Usuario/5
        public void Delete(int id)
        {
            Models.ToastDataContext dc = new Models.ToastDataContext();
            var x = (from f in dc.Usuarios
                     where f.Id == id
                     select f).Single();

            dc.Usuarios.DeleteOnSubmit(x);
            dc.SubmitChanges();
        }
        // GET api/usuario
        public IEnumerable <Models.User> Get()
        {
            Models.ToastDataContext dc = new Models.ToastDataContext();
            var r = from f in dc.Usuarios
                    select new Models.User {
                Id = f.Id, Nome = f.Nome, Uri = f.Uri
            };

            return(r.ToList());
        }
        // PUT api/Usuario/5
        public void Put(int id, [FromBody] string value)
        {
            Models.User             user = JsonConvert.DeserializeObject <Models.User>(value);
            Models.ToastDataContext dc   = new Models.ToastDataContext();
            var x =
                (from f in dc.Usuarios
                 where f.Id == id
                 select f).Single();

            x.Nome = user.Nome;
            x.Uri  = user.Uri;
            dc.SubmitChanges();
        }