📅 Day 5：订单提交与支付模拟

✅ 今日目标：

• 创建 Order 和 OrderItem 模型
• 实现从购物车生成订单的功能
• 模拟支付流程（成功/失败页面）
• 添加订单状态跟踪（如“待付款”、“已发货”等）
• 提交 Git 版本记录进度

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🧩 功能概览

页面	功能
/Checkout/Index.cshtml	确认订单信息
/Checkout/Success.cshtml	支付成功页面
/Checkout/Failed.cshtml	支付失败页面
/Orders/Index.cshtml	我的订单列表
数据库模型	Order, OrderItem

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🛠️ 知识点预览

技术	内容
数据模型	Order 表示订单，OrderItem 表示订单中的商品
购物车转订单	将 Session 中的购物车数据保存为订单
支付模拟	使用按钮或自动跳转模拟支付结果
用户身份验证	只有登录用户才能下单
UI 设计	Bootstrap + Razor Pages 构建订单确认页

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🧱 第一步：创建订单相关模型

在 Models 文件夹中创建以下两个类：

✅ Order.cs

using System.ComponentModel.DataAnnotations;namespace ECommercePlatform.Models
{public enum OrderStatus{Pending,Paid,Shipped,Completed,Cancelled}public class Order{public int Id { get; set; }[Required]public string UserId { get; set; } = string.Empty;public DateTime OrderDate { get; set; } = DateTime.Now;public decimal TotalAmount { get; set; }public OrderStatus Status { get; set; } = OrderStatus.Pending;public List<OrderItem> Items { get; set; } = new();}
}

✅ OrderItem.cs

namespace ECommercePlatform.Models
{public class OrderItem{public int Id { get; set; }public int ProductId { get; set; }public string ProductName { get; set; } = string.Empty;public decimal Price { get; set; }public int Quantity { get; set; }public decimal TotalPrice => Price * Quantity;public int OrderId { get; set; }public Order Order { get; set; } = null!;}
}

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🧰 第二步：更新数据库上下文

打开 ApplicationDbContext.cs 并添加以下代码：

public DbSet<Order> Orders { get; set; }
public DbSet<OrderItem> OrderItems { get; set; }

然后执行迁移命令：

dotnet ef migrations add AddOrderAndOrderItem
dotnet ef database update

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🛒 第三步：创建订单服务逻辑

✅ 创建 Services/IOrderService.cs

using ECommercePlatform.Models;public interface IOrderService
{Task<int> CreateOrderFromCart(string userId, IList<CartItem> cartItems);Task<IList<Order>> GetOrdersByUser(string userId);Task<Order?> GetOrderById(int id, string userId);
}

✅ 创建 Services/OrderService.cs

using Microsoft.AspNetCore.Identity;
using ECommercePlatform.Models;
using ECommercePlatform.Services;public class OrderService : IOrderService
{private readonly ApplicationDbContext _context;private readonly UserManager<IdentityUser> _userManager;public OrderService(ApplicationDbContext context, UserManager<IdentityUser> userManager){_context = context;_userManager = userManager;}public async Task<int> CreateOrderFromCart(string userId, IList<CartItem> cartItems){if (cartItems.Count == 0) throw new ArgumentException("购物车为空");var order = new Order{UserId = userId,OrderDate = DateTime.Now,TotalAmount = cartItems.Sum(i => i.TotalPrice),Items = cartItems.Select(i => new OrderItem{ProductId = i.ProductId,ProductName = i.Name,Price = i.Price,Quantity = i.Quantity}).ToList()};_context.Orders.Add(order);await _context.SaveChangesAsync();return order.Id;}public async Task<IList<Order>> GetOrdersByUser(string userId){return await _context.Orders.Include(o => o.Items).Where(o => o.UserId == userId).OrderByDescending(o => o.OrderDate).ToListAsync();}public async Task<Order?> GetOrderById(int id, string userId){return await _context.Orders.Include(o => o.Items).FirstOrDefaultAsync(o => o.Id == id && o.UserId == userId);}
}

注册服务到 Program.cs：

builder.Services.AddScoped<IOrderService, OrderService>();

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📋 第四步：创建订单确认页面（Checkout/Index）

✅ Checkout/Index.cshtml.cs

using Microsoft.AspNetCore.Mvc.RazorPages;
using ECommercePlatform.Services;
using ECommercePlatform.Models;namespace ECommercePlatform.Pages.Checkout
{[Authorize]public class IndexModel : PageModel{private readonly IShoppingCartService _cartService;private readonly UserManager<IdentityUser> _userManager;public IndexModel(IShoppingCartService cartService, UserManager<IdentityUser> userManager){_cartService = cartService;_userManager = userManager;}public IList<CartItem> CartItems { get; set; } = new List<CartItem>();public decimal TotalPrice { get; set; }public async Task<IActionResult> OnGetAsync(){CartItems = _cartService.GetCartItems();TotalPrice = _cartService.GetTotalPrice();if (CartItems.Count == 0){return RedirectToPage("/Cart/Index");}return Page();}public async Task<IActionResult> OnPostAsync(){var user = await _userManager.GetUserAsync(User);if (user == null) return NotFound();var cartItems = _cartService.GetCartItems();if (cartItems.Count == 0) return BadRequest();// 创建订单var orderService = HttpContext.RequestServices.GetService<IOrderService>();var orderId = await orderService.CreateOrderFromCart(user.Id, cartItems);// 清空购物车_cartService.ClearCart();return RedirectToPage("/Checkout/Success", new { id = orderId });}}
}

✅ Checkout/Index.cshtml

@page
@model ECommercePlatform.Pages.Checkout.IndexModel<h2>确认订单</h2><table class="table"><thead><tr><th>名称</th><th>单价</th><th>数量</th><th>总价</th></tr></thead><tbody>@foreach (var item in Model.CartItems){<tr><td>@item.Name</td><td>$@item.Price</td><td>@item.Quantity</td><td>$@item.TotalPrice</td></tr>}</tbody>
</table><h4>总计：$@Model.TotalPrice</h4><form method="post"><button type="submit" class="btn btn-success">立即支付</button>
</form>

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✅ 第五步：创建支付成功页面（Checkout/Success）

✅ Success.cshtml.cs

using Microsoft.AspNetCore.Mvc.RazorPages;namespace ECommercePlatform.Pages.Checkout
{public class SuccessModel : PageModel{public void OnGet(int id){// 这里可以显示订单编号或详细信息}}
}

✅ Success.cshtml

@page
@model ECommercePlatform.Pages.Checkout.SuccessModel<h2>✅ 支付成功！</h2>
<p>您的订单已提交。订单号：@Request.Query["id"]</p>
<a asp-page="/Orders/Index" class="btn btn-primary">查看我的订单</a>

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❌ 第六步：创建支付失败页面（Checkout/Failed）

✅ Failed.cshtml.cs

using Microsoft.AspNetCore.Mvc.RazorPages;namespace ECommercePlatform.Pages.Checkout
{public class FailedModel : PageModel{public void OnGet(){}}
}

✅ Failed.cshtml

@page
@model ECommercePlatform.Pages.Checkout.FailedModel<h2>❌ 支付失败</h2>
<p>请返回重新尝试支付。</p>
<a asp-page="/Cart/Index" class="btn btn-warning">返回购物车</a>

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📦 第七步：创建我的订单页面（Orders/Index）

✅ Orders/Index.cshtml.cs

using Microsoft.AspNetCore.Mvc.RazorPages;
using ECommercePlatform.Services;
using ECommercePlatform.Models;
using Microsoft.AspNetCore.Identity;namespace ECommercePlatform.Pages.Orders
{[Authorize]public class IndexModel : PageModel{private readonly IOrderService _orderService;private readonly UserManager<IdentityUser> _userManager;public IndexModel(IOrderService orderService, UserManager<IdentityUser> userManager){_orderService = orderService;_userManager = userManager;}public IList<Order> Orders { get; set; } = new List<Order>();public async Task OnGetAsync(){var user = await _userManager.GetUserAsync(User);if (user != null){Orders = await _orderService.GetOrdersByUser(user.Id);}}}
}

✅ Orders/Index.cshtml

@page
@model ECommercePlatform.Pages.Orders.IndexModel<h2>我的订单</h2>@if (Model.Orders.Count == 0)
{<p>暂无订单。</p>
}
else
{<table class="table"><thead><tr><th>订单号</th><th>日期</th><th>总金额</th><th>状态</th><th>操作</th></tr></thead><tbody>@foreach (var order in Model.Orders){<tr><td>@order.Id</td><td>@order.OrderDate.ToShortDateString()</td><td>$@order.TotalAmount</td><td>@order.Status</td><td><a asp-page="/Orders/Details" asp-route-id="@order.Id" class="btn btn-info btn-sm">查看详情</a></td></tr>}</tbody></table>
}

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📦 第八步：提交 Git 版本

git add .
git commit -m "Day5: Added order submission and payment simulation with order status tracking"

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📝 今日总结

今天你完成了：

✅ 创建 Order 和 OrderItem 模型
✅ 实现从购物车生成订单的功能
✅ 模拟支付流程（成功/失败页面）
✅ 订单状态跟踪（Pending、Paid、Shipped 等）
✅ 提交版本控制记录

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📆 明日计划（Day6）

我们将进入 后台管理系统开发阶段：

• 创建管理员页面
• 实现商品管理（CRUD）
• 实现订单管理（查看、状态变更）
• 权限控制（仅管理员可见）