EFCore代码实践

参考：https://www.cnblogs.com/Wddpct/p/6835574.html

 控制台程序依赖注入参考：https://www.cnblogs.com/Wddpct/p/7219205.html 

1、模型定义

namespace Domain
{
    public class Blog
    {
        public Blog()
        {
            Posts = new List<Post>();
        }
        public int BlogId { get; set; }
        public string Url { get; set; }
        public string Title { get; set; }
        public string Author { get; set; }
        public DateTime CreateTime { get; set; }
        public virtual List<Post> Posts { get; set; }

        public void AddPsot(Post post)
        {
            if (Posts == null)
            {
                Posts = new List<Post>();
            }

            Posts.Add(post);
        }
    }
}

namespace Domain
{
    public class Post
    {
        public int PostId { get; set; }
        public string Title { get; set; }
        public string Content { get; set; }

        public int BlogId { get; set; }
        public virtual Blog Blog { get; set; }
    }
}

2、数据访问

using Domain;
using Microsoft.EntityFrameworkCore;
using System;

namespace CoreEfDAL
{
    public class ForumContext : DbContext
    {
        public ForumContext(DbContextOptions<ForumContext> options)
            : base(options)
        {

        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
            modelBuilder.Entity<Blog>().Property(b => b.Url).HasMaxLength(500);
            modelBuilder.Entity<Blog>().Property(b => b.Title).HasMaxLength(100);
            modelBuilder.Entity<Blog>().Property(b => b.Author).HasMaxLength(20);

            modelBuilder.Entity<Blog>()
                .HasMany(b => b.Posts)
                .WithOne(b => b.Blog);
        }

        public DbSet<Blog> Blogs { get; set; }
        public DbSet<Post> Posts { get; set; }
    }
}

3、单元测试

using CoreEfDAL;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Microsoft.EntityFrameworkCore.Extensions;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Domain;
using System;
using System.IO;

namespace CoreEfDAL_Test
{
    [TestClass]
    public class UnitTest1
    {
        private ForumContext GetDB()
        {
            ConfigurationBuilder cfgBuilder = new ConfigurationBuilder();
            cfgBuilder.SetBasePath(Directory.GetCurrentDirectory())
                      .AddJsonFile("appsettings.json");

            var configuration = cfgBuilder.Build();
            var conString = configuration.GetConnectionString("myblog");

            var serviceCollection = new ServiceCollection(); 
            serviceCollection.AddDbContext<ForumContext>(c => c.UseSqlServer(conString));

            var db = serviceCollection.BuildServiceProvider().GetService<ForumContext>();
            return db;
        }

        [TestMethod]
        public void AddBolgs_Test()
        {
            var db = GetDB();
            var blog = new Blog {
                Url = "http://blogs.msdn.com/adonet",
                Title = "测试标题121212111", Author = "王五",
                CreateTime = DateTime.Now };

            var post1 = new Post();
            post1.Content = "ddddddd";
            post1.Title = "tttttttt";

            var post2 = new Post();
            post2.Content = "dddxxxxdddd";
            post2.Title = "ttttddddd";

            var post3 = new Post();
            post3.Content = "2345sdfsd";
            post3.Title = "dghdfghfgh";

            blog.AddPsot(post1);
            blog.AddPsot(post2);
            blog.AddPsot(post3);

            db.Blogs.Add(blog);
            var count = db.SaveChanges();
            Console.WriteLine("{0} records saved to database", count);
        }
    }
}

基于内存数据库的测试

[TestMethod]
        public void AddDepartment_Test()
        {
            var options = new DbContextOptionsBuilder<PortalContext>()
                .UseInMemoryDatabase(databaseName: "portaldb")
                .Options;

            using (var context = new PortalContext(options))
            {
                Department dp = new Department();
                dp.Id = "100008";
                dp.Name = "根目录";
                dp.ParentId = "";
                dp.IsDeleted = false;

                context.Departments.Add(dp);
                var count = context.SaveChanges();
                Console.WriteLine("{0} records saved to database", count);

                var d = context.Departments.Find("100008");
                Console.WriteLine(d.Name);
            } 
        }

4、API调用

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using CoreEfDAL;
using Domain;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Newtonsoft.Json;

namespace CoreEfWeb.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class BlogsController : ControllerBase
    {
        private readonly ForumContext _dbContext;
        public BlogsController(ForumContext dbContext)
        {
            _dbContext = dbContext;
        }

        private JsonResult Json(object data)
        {
            JsonSerializerSettings settings = new JsonSerializerSettings();
            settings.MaxDepth = 2;
            settings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore; //忽略循环引用
            return new JsonResult(data, settings);
        }

        [HttpGet]
        public JsonResult Get()
        {
            var blogs = _dbContext.Blogs.Include(b => b.Posts).ToList();
            return Json(blogs);
        }

        [HttpGet("{id}")]
        public JsonResult Get(int id)
        {
            var blog = _dbContext.Blogs.Include(b => b.Posts).FirstOrDefault(b => b.BlogId == id);
            return Json(blog);
        }

        [HttpPost]
        public void Post([FromBody] Blog blog)
        {
            _dbContext.Blogs.Add(blog);
            _dbContext.SaveChanges();
        }

        [HttpPut("{id}")]
        public void Put(int id, [FromBody] Blog blog)
        {
            var blogDomain = _dbContext.Blogs.FirstOrDefault(b => b.BlogId == id);
            if (blogDomain != null)
            {
                blogDomain.Title = blog.Title;
                blogDomain.Author = blog.Author;
                blogDomain.Url = blog.Url;
                _dbContext.SaveChanges();
            }
        }

        [HttpPut("{id}/author")]
        public void Put(int id, [FromBody] ModifyBlogAuthorRequest request)
        {
            var blogDomain = _dbContext.Blogs.FirstOrDefault(b => b.BlogId == id);
            if (blogDomain != null)
            {
                blogDomain.Author = request.NewAuthor;
                blogDomain.CreateTime = DateTime.Now;
                _dbContext.SaveChanges();
            }
        }

        [HttpDelete("{id}")]
        public void Delete(int id)
        {
            var blogDomain = _dbContext.Blogs.FirstOrDefault(b => b.BlogId == id);
            if (blogDomain != null)
            {
                _dbContext.Blogs.Remove(blogDomain);
                _dbContext.SaveChanges();
            }
        }
    }

    public class ModifyBlogAuthorRequest
    {
        public string NewAuthor { get; set; }
    }
}

5、其他

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.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using CoreEfDAL;
using Microsoft.EntityFrameworkCore;
using Newtonsoft.Json;

namespace CoreEfWeb
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<ForumContext>(c => c.UseSqlServer(Configuration.GetConnectionString("myblog")));
            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseMvc();
        }
    }
}

appsettings.json 文件
{
  "ConnectionStrings": {
    "myblog": "server=.;uid=sa;pwd=sa123456;database=efcoretest"
  }
}

迁移命令
Add-Migration init  --迁移
Updata-Database  --更新数据库