经过一段时间的准备，新的一期【ASP.NET Core MVC开发实战之商城系统】已经开始，在之前的文章中，讲解了商城系统的整体功能设计，页面布局设计，环境搭建，系统配置，及首页【商品类型，banner条，友情链接，降价促销，新品爆款】，商品列表页面，商品详情等功能的开发，今天继续讲解购物车功能开发，仅供学习分享使用，如有不足之处，还请指正。

购物车功能说明

在首页或者商品列表页面，如果用户对商品感兴趣，可以点击快捷方式，将商品加入购物车；或者在商品详情页面，选择对应的商品参数后，将商品加入购物车。商品加入购物车的渠道是有多种，而用户也可以对已经加入购物车的商品进行购买，或者删除购物车。每一个用户都有各自的购物车，相互之间独立，所以购物车功能需要用户先进行登录，才能查看。

购物车功能设计

根据购物车功能说明，购物车主要显示已添加的商品列表，并可以删除，或者选择商品进行购买，设计页面如下所示：

购物车功能开发

购物车主要展示用户选择的商品信息。

1. 数据表创建

购物车表EB_Cart主要用于存储商品信息，用户信息，数量，及个人喜好等内容，如下所示：

购物车表创建语句如下所示：

sql 复制代码

CREATE TABLE [dbo].[EB_Cart](
	[Id] [bigint] IDENTITY(1,1) NOT NULL,
	[ProductId] [bigint] NULL,
	[CustomerId] [bigint] NULL,
	[Quantity] [int] NULL,
	[Remark] [varchar](200) NULL,
	[CreateTime] [datetime] NULL,
	[CreateUser] [varchar](50) NULL,
	[LastEditTime] [datetime] NULL,
	[LastEditUser] [varchar](50) NULL
) ON [PRIMARY]

2. 购物车实体创建

购物车实体和数据表结构保持一致，方便进行映射。如下所示：

cs 复制代码

using SqlSugar;
 
namespace EasyBuyShop.Models
{
    /// <summary>
    /// 购物车
    /// </summary>
    [SugarTable("EB_Cart")]
    public class Cart:EntityModel
    {
        public long ProductId { get; set; }
 
        public long CustomerId { get; set; }
 
        /// <summary>
        /// 数量
        /// </summary>
        public int Quantity { get; set; }
 
        public string Remark { get; set; }
    }
}

3. 数据处理层DAL

购物车列表，主要包括添加购物车，删除，查询等功能，DAL层代码如下所示：

cs 复制代码

using EasyBuyShop.Models;
using EasyBuyShop.Utils;
 
namespace EasyBuyShop.DAL
{
    public class CartDal:BaseDal
    {
        /// <summary>
        /// 获取购物车列表
        /// </summary>
        /// <param name="userId"></param>
        /// <returns></returns>
        public List<Cart> GetCartListByUserId(long userId)
        {
            try
            {
                using (var db = this.GetDb(BaseDal.ConnStr))
                {
                    return db.Queryable<Cart>().Where(r => r.CustomerId == userId).ToList();
                }
            }
            catch (Exception ex)
            {
                LogHelper.Fatal(ex.Message);
                return new List<Cart>();
            }
        }
 
        public int DeleteById(long id)
        {
            try
            {
                using (var db = this.GetDb(BaseDal.ConnStr))
                {
                    int cnt = db.Deleteable<Cart>(r => r.Id == id).ExecuteCommand();
                    return cnt;
                }
            }
            catch (Exception ex)
            {
                LogHelper.Fatal(ex.Message);
                return -1;
            }
        }
 
        public Cart GetCart(long id)
        {
            try
            {
                using (var db = this.GetDb(BaseDal.ConnStr))
                {
                    return db.Queryable<Cart>().First(r => r.Id == id);
                }
            }
            catch (Exception ex)
            {
                LogHelper.Fatal(ex.Message);
                return null;
            }
        }
    }
}

4. 控制器获取

控制器方法主要包括添加购物车【1.首页或商品列表快捷添加购物车 2.商品详情页面添加购物车】，查询购物车，删除购物车，代码如下所示：

cs 复制代码

using EasyBuyShop.DAL;
using EasyBuyShop.Models;
using Microsoft.AspNetCore.Mvc;
 
namespace EasyBuyShop.Controllers
{
    /// <summary>
    /// 购物车控制器
    /// </summary>
    public class CartController : Controller
    {
        /// <summary>
        /// 购物车列表页面
        /// </summary>
        /// <returns></returns>
        public IActionResult Index()
        {
            
            var userId = HttpContext.Session.GetInt32("userid");
            if (userId == null)
            {
               return Redirect("/Auth/login");
            }
            var cartDal = new CartDal();
            var productDal = new ProductDal();
            var cartList = cartDal.GetCartListByUserId((long)userId);
            var products = productDal.GetProductListByIds(cartList.Select(r => r.ProductId).ToList());
            ViewData["CartList"] = cartList;
            ViewData["ProductList"]= products;
            var username = HttpContext.Session.GetString("username");
            var realName = HttpContext.Session.GetString("realname");
            ViewData["Username"] = username;
            ViewData["RealName"] = realName;
            return View();
        }
 
        /// <summary>
        /// 首页或商品列表，快捷加入购物车
        /// </summary>
        /// <param name="productId"></param>
        /// <returns></returns>
        [HttpPost]
        public IActionResult Add(int productId)
        {
            Msg msg = new Msg();
            var userId = HttpContext.Session.GetInt32("userid");
            var userName= HttpContext.Session.GetString("username");
            if (userId == null)
            {
                msg.code = -1;
                msg.message = "尚未登录";
                return Json(msg);
            }
            var productDal = new ProductDal();
            var product = productDal.GetProduct(productId);
            if (product != null)
            {
                var cartDal = new CartDal();
                var cart=new Cart();
                cart.ProductId = productId;
                cart.CustomerId = userId.Value;
                cart.Quantity = 1;
                cart.Remark= string.Empty;
                cart.CreateUser = userName;
                cart.CreateTime=DateTime.Now;
                cart.LastEditUser = userName;
                cart.LastEditTime = DateTime.Now;
                int id = cartDal.InsertT<Cart>(cart);
                if(id > 0)
                {
                    msg.code = 0;
                    msg.message = "成功";
                    return Json(msg);
                }
                else
                {
                    msg.code = -1;
                    msg.message = "加入购物车失败";
                    return Json(msg);
                }
            }
            else
            {
                msg.code = -1;
                msg.message = "商品不存在";
                return Json(msg);
            }
            
        }
 
        /// <summary>
        /// 商品详情页面加入购物车
        /// </summary>
        /// <returns></returns>
        [HttpPost]
        public IActionResult AddWithForm()
        {
            Msg msg = new Msg();
            var userId = HttpContext.Session.GetInt32("userid");
            var userName = HttpContext.Session.GetString("username");
            if (userId == null)
            {
                msg.code = -1;
                msg.message = "尚未登录";
                return Json(msg);
            }
            var productId =long.Parse( Request.Form["productId"]);
            var quantity = int.Parse(Request.Form["quantity"]);
            var color = Request.Form["color"];
            var size = Request.Form["size"];
            var remark = $"颜色：{color},大小：{size}";
            var productDal = new ProductDal();
            var product = productDal.GetProduct(productId);
            if (product != null)
            {
                var cartDal = new CartDal();
                var cart = new Cart();
                cart.ProductId = productId;
                cart.CustomerId = userId.Value;
                cart.Quantity = quantity;
                cart.Remark = remark;
                cart.CreateUser = userName;
                cart.CreateTime = DateTime.Now;
                cart.LastEditUser = userName;
                cart.LastEditTime = DateTime.Now;
                int id = cartDal.InsertT<Cart>(cart);
                if (id > 0)
                {
                    msg.code = 0;
                    msg.message = "成功";
                }
                else
                {
                    msg.code = -1;
                    msg.message = "加入购物车失败";
                }
            }
            else
            {
                msg.code = -1;
                msg.message = "商品不存在";
            }
            return Redirect("/Cart/Index");
 
        }
 
        /// <summary>
        /// 移除购物车
        /// </summary>
        /// <param name="Id"></param>
        /// <returns></returns>
        public ActionResult Delete(int Id)
        {
            var cartDal =new CartDal();
            if(cartDal.DeleteById(Id) > 0)
            {
                //成功
            }
            else
            {
                //删除失败
            }
            return View();
        }
    }
}

5. 视图层展示

在Views/Cart/Index.cshtml购物车视图中，接收控制器传递的参数。如下所示：

html 复制代码

@{
    var totalPrice = 0.0M;
}
<div class="content-wrap">
    <div class="content">
        <!-- shopping-cart-area start -->
        <div class="cart-area ptb-100">
            <form action="/Purchase/BuyWithCart" method="post">
                <div class="container">
                    <div class="row">
                        <div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
 
                            <div class="table-content table-responsive">
                                <table>
                                    <thead>
                                        <tr>
                                            <th class="product-check">选择</th>
                                            <th class="product-price">图片</th>
                                            <th class="product-name">产品名称</th>
                                            <th class="product-price">价格</th>
                                            <th class="product-price">优惠价格</th>
                                            <th class="product-quantity">数量</th>
                                            <th class="product-subtotal">总计</th>
                                            <th class="product-name">删除</th>
                                        </tr>
                                    </thead>
                                    <tbody>
                                        @{
                                            var cartList = ViewData["CartList"] as List<Cart>;
                                            var productList = ViewData["ProductList"] as List<Product>;
                                            if (cartList.Count > 0)
                                            {
                                                foreach (var cart in cartList)
                                                {
                                                    var product = productList.FirstOrDefault(r => r.Id == cart.ProductId);
                                                    totalPrice = totalPrice + (product.PreferentialPrice * cart.Quantity);
                                                    <tr>
                                                        <td class="product-check">
                                                            <input type="checkbox" value="@(cart.Id)" name="chkCart" style="width:25px;height:25px;" checked="checked" onchange="javascript:checkCartProduct(this);" />
                                                        </td>
                                                        <td class="product-thumbnail">
                                                            <a href="/Product/Detail/@(product.Id)"><img src="@(product.ImageUrl)" alt="" width="100" height="100"></a>
                                                        </td>
                                                        <td class="product-name">
                                                            <a href="/Product/Detail/@(product.Id)">@product.Name</a>
                                                            <br />
                                                            <span style="font-size:12px; color:lightgray">备注：@(string.IsNullOrEmpty(cart.Remark) ? "无" : cart.Remark)</span>
                                                        </td>
                                                        <td class="product-price"><span class="amount">@(Math.Round(product.Price, 2))</span></td>
                                                        <td class="product-price"><span class="amount">@(Math.Round(product.PreferentialPrice, 2))</span></td>
                                                        <td class="product-quantity">
                                                            <input value="@(cart.Quantity)" type="number">
                                                        </td>
                                                        <td class="product-subtotal">@(Math.Round(product.PreferentialPrice * cart.Quantity, 2))</td>
                                                        <td class="product-remove">
                                                            <a href="/Cart/Delete/@(cart.Id)">
                                                                <i class="fa fa-times"><font style="font-size:14px;">删除</font></i>
                                                            </a>
                                                        </td>
                                                    </tr>
                                                }
                                            }
                                            else
                                            {
                                                <tr><td colspan="7">购物车暂无商品</td></tr>
                                            }
                                        }
                                    </tbody>
                                </table>
                            </div>
 
                        </div>
                    </div>
                    <div class="row tax-coupon-div">
                        <div class="col-md-7 col-sm-12 col-xs-12">
                        </div>
                        <div class="col-md-5 col-sm-12 col-xs-12">
                            <div class="cart-total">
                                <ul>
                                    <li class="cart-black">总计<span>@totalPrice</span></li>
                                </ul>
                                <div class="cart-total-btn">
                                    <div class="cart-total-btn1 f-left">
                                    </div>
                                    <div class="cart-total-btn2 f-right">
                                        <input type="submit" value="购买" class="go-btn" onclick="javascript:return checkSubmit();" style="background-color: rgb(255, 80, 0);border-width:0px;margin-top:5px;" />
                                    </div>
                                </div>
                            </div>
                        </div>
                    </div>
                </div>
            </form>
        </div>
        <!-- shopping-cart-area end -->
    </div>
    <!-- content end -->
</div>
<!-- content-wrap end -->
<script src="~/js/shop.js"></script>

购物车页面展示

运行程序，点击登录，在登录成功后，在右上角个人名称，点击下拉菜单，选择购物车，然后打开购物车页面，如下所示：

以上就是ASP.NET Core MVC开发实战之商城系统第五部分内容，后续将继续介绍其他模块，敬请期待。

[回馈]ASP.NET Core MVC开发实战之商城系统(五)

购物车功能说明

购物车功能设计

购物车功能开发

1. 数据表创建

2. 购物车实体创建

3. 数据处理层DAL

4. 控制器获取

5. 视图层展示

购物车页面展示