如何在asp.net webapi中访问产品的ID

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Web.Http;
using System.Web.Mvc;
using OnlineStoreApi.Models;

namespace OnlineStoreApi.Controllers
{
    public class ProductController : ApiController
    {
        /*private readonly mystoreEntities1 _myObj = new mystoreEntities1();*/


        #region Variables
        DataClasses1DataContext _context = new DataClasses1DataContext();
        ProductModel products;
        #endregion
        public IEnumerable<ProductModel> GetALLProducts()
        {


            var prods = from item in _context.spGetProducts().ToList()
                        select new ProductModel
                        {
                            Id = item.id,
                            ProductTypeId = item.ProductTypeId,
                            VendorId = item.VendorId,
                            OldPrice = item.OldPrice,
                            Price = item.Price,
                            ProductCost = item.ProductCost,
                            PictureId=item.PictureId,
                            PictureBinary=item.PictureBinary.ToArray(),
                            MimeType=item.MimeType
                        };
                      return prods;
        }


        public IHttpActionResult GetProduct(int id)
        {
            products = new ProductModel();
            var product = products.FirstOrDefault((p) => p.Id == id);
            if (product == null)
            {
                return NotFound();
            }
            return Ok(product);
        }


    }
}
using System;
using System.Collections;
using S