// POST api/FacturaMateriales
 public void Post([FromBody] FacturaMateriales FacturaMateriales)
 {
     using (TEConstruyeEntities entities = new TEConstruyeEntities())
     {
         entities.FacturaMateriales.Add(FacturaMateriales);
         entities.SaveChanges();
     }
 }
        // PUT api/FacturaMateriales/?IDFactura?IDMaterial
        public void Put(int IDFactura, int IDMaterial, [FromBody] FacturaMateriales FacturaMateriales)
        {
            using (TEConstruyeEntities entities = new TEConstruyeEntities())
            {
                var entity = entities.FacturaMateriales.FirstOrDefault(controller => controller.IDFactura == IDFactura && controller.IDMaterial == IDMaterial);
                entity.Neto = FacturaMateriales.Neto;

                entities.SaveChanges();
            }
        }