我正在尝试通过学习 Udemy 上的课程来实现电子商务网站。我正在尝试更新我的数据库。我创建了一个名为 ProductCategories 的新表，它允许 Products 和 Categories 之间的多对多关系。问题是我的代码生成了表格，并将产品添加到Product 表，但是，它cannot 填充ProductCategories 表。
类别.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace shopapp.entity
{
public class Category
{
public int CategoryId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public List<ProductCategory> ProductCategories { get; set; }
}
}
产品.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace shopapp.entity
{
public class Product
{
public int ProductId { get; set; }
public string Name { get; set; }
public double Price { get; set; }
public string Description { get; set; }
public string ImageUrl { get; set; }
public bool IsApproved { get; set; }
public int CategoryId { get; set; }
public List<ProductCategory> ProductCategories { get; set; }
}
}
ProductCategory.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace shopapp.entity
{
public class ProductCategory
{
public int CategoryId { get; set; }
public Category Category { get; set; }
public int ProductId { get; set; }
public Product Product { get; set; }
}
}
DbContext.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using shopapp.entity;
namespace shopapp.data.Concrete.EfCore
{
public class ShopContext:DbContext
{
public DbSet<Product> Products { get; set; }
public DbSet<Category> Categories { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
// TODO
// check MySql version
optionsBuilder.UseMySQL("Server=localhost;port=3306;Database=shopapp2;Uid=root;Pwd=admin;");
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<ProductCategory>()
.HasOne(pc => pc.Category)
.WithMany(pc => pc.ProductCategories)
.HasForeignKey(pc => pc.ProductId);
modelBuilder.Entity<ProductCategory>()
.HasOne(pc => pc.Product)
.WithMany(pc => pc.ProductCategories)
.HasForeignKey(pc => pc.CategoryId);
}
}
}
SeedDatabse.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using shopapp.entity;
namespace shopapp.data.Concrete.EfCore
{
public static class SeedDatabase
{
public static void Seed()
{
using(var context = new ShopContext())
{
Console.WriteLine(context.Database.GetPendingMigrations().Count());
if (context.Database.GetPendingMigrations().Count() == 0)
{
Console.WriteLine(context.Categories.Count());
Console.WriteLine(context.Products.Count());
if (context.Categories.Count() == 0)
{
context.Categories.AddRange(Categories);
Console.WriteLine("Categories added!");
//Console.WriteLine("Products and ProductCategories added!");
}
if (context.Products.Count() == 0)
{
context.Products.AddRange(Products);
context.AddRange(ProductCategories); // we do not need to specify Product or category
}
context.SaveChanges();
}
}
}
private static Category[] Categories = {
new Category(){ CategoryId=4, Name = "Fashion", Description="Fashion Category"},
new Category(){ CategoryId=5, Name = "Supermarket", Description="Supermarket Category"},
new Category(){ CategoryId=6, Name = "Mom and Baby", Description="Mom and Baby Category"}
};
private static Product[] Products = {
new Product(){ProductId=11, Name = "Test Product 1", Price=1000, Description="Test Data", ImageUrl="test.jpg", IsApproved=true},
new Product(){ProductId=12, Name = "Test Product 2", Price=1200, Description="Test Data", ImageUrl="test.jpg", IsApproved=true},
new Product(){ProductId=13, Name = "Test Product 3", Price=1400, Description="Test Data", ImageUrl="test.jpg", IsApproved=false}
};
private static ProductCategory[] ProductCategories =
{
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]},
new ProductCategory(){CategoryId = Categories[0].CategoryId, Category=Categories[0], ProductId = Products[0].ProductId, Product=Products[2]}
};
}
}
Startup.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using shopapp.business.Abstract;
using shopapp.business.Concrete;
using shopapp.data.Abstract;
using shopapp.data.Concrete.EfCore;
namespace shopapp.webui
{
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
// IProductRepository'yi uygulama çağırıldığı zaman EfCoreProductRepository nesne oluşturulup gönderilecek.
services.AddScoped<IProductRepository,EfCoreProductRepository>();
services.AddScoped<IProductService,ProductManager>();
services.AddControllersWithViews();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
// checks if the app is in development process
// Call your Seed method
// env is a global variable, you can change this in
// /shopapp\\.vscode\\launch.json file
// by changing
/*
"env": {
"ASPNETCORE_ENVIRONMENT": "Development"
},
*/
// to
/*"env": {
"ASPNETCORE_ENVIRONMENT": "Production"
},*/
// when you publish your website
if (env.IsDevelopment())
{
SeedDatabase.Seed();
app.UseDeveloperExceptionPage();
}
else
{
app.UseExceptionHandler("/Home/Error");
// The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
app.UseHsts();
}
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllerRoute(
name: "products",
pattern: "products/{category?}",
defaults: new {controller="Shop", action="list"}
);
endpoints.MapControllerRoute(
name: "default",
pattern: "{controller=Home}/{action=Index}/{id?}");
});
}
}
}
我正在使用 .Net 7.0.102.