public IHttpActionResult Delete(int id)
 {
     if (id <= 0)
     {
         return(BadRequest("Not a valid student id"));
     }
     using (var ctx = new ProductStoreDB())
     {
         var product = ctx.Products
                       .Where(p => p.ProductID == id)
                       .FirstOrDefault();
         ctx.Entry(product).State = System.Data.Entity.EntityState.Deleted;
         ctx.SaveChanges();
     }
     return(Ok());
 }