ef.core Mysql

• Entity层

 using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Runtime.Serialization;
 using System.Text;

 namespace Entity.Core
 {
     /// <summary>
     /// DB表基础属性
     /// </summary>
     public abstract class BaseEntity<T>
     {
         public BaseEntity()
         {
             CreteTime = DateTime.Now;
         }
         /// <summary>
         /// 主键Id
         /// </summary>
         [DataMember]
         [Key]
         public T Id { get; set; }

         /// <summary>
         /// DB版号,Mysql详情参考;http://www.cnblogs.com/shanyou/p/6241612.html
         /// </summary>
         //[Timestamp]//Mysql不允许byte[]类型上标记TimeStamp/RowVersion，这里使用DateTime类型配合标记ConcurrencyCheck达到并发控制
         [ConcurrencyCheck]
         public DateTime RowVersion { get; set; }

         /// <summary>
         /// 创建时间
         /// </summary>
         public DateTime CreteTime { get; set; }
     }
 }

BaseEntity

 using Entity.Core;
 using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Text;

 namespace Entity.Table
 {
     /// <summary>
     /// 商品类
     /// </summary>
     public class Product : BaseEntity<long>
     {
         /// <summary>
         /// 名称
         /// </summary>
         [StringLength()]
         [Required]
         public string Name { get; set; }

         /// <summary>
         /// 描述
         /// </summary>
         [StringLength()]
         [Required]
         public string Description { get; set; }

         /// <summary>
         /// 类别
         /// </summary>
         [Range(, int.MaxValue)]
         public int Category { get; set; }

         /// <summary>
         /// 原价
         /// </summary>
         [Required]
         public decimal Price { get; set; }

         /// <summary>
         /// 现价
         /// </summary>
         public decimal Discount { get; set; }
     }
 }

Product

• 在DAL层添加以下引用

Microsoft.EntityFrameworkCore

Microsoft.EntityFrameworkCore.Tools

Microsoft.EntityFrameworkCore.Relational

Pomelo.EntityFrameworkCore.MySql

 using Entity;
 using Entity.Table;
 using Microsoft.EntityFrameworkCore;
 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;

 namespace DAL
 {
     public class ProductContext : DbContext
     {
         //https://docs.microsoft.com/en-us/aspnet/core/data/ef-mvc/complex-data-model
         public ProductContext(DbContextOptions<ProductContext> options) : base(options)
         {
             //在此可对数据库连接字符串做加解密操作
         }

         public DbSet<Person> Person { get; set; }
         public DbSet<Product> Product { get; set; }

         protected override void OnModelCreating(ModelBuilder modelBuilder)
         {
             base.OnModelCreating(modelBuilder);
         }
     }
 }

DbContext

• Service 层

添加引用 Microsoft.EntityFrameworkCore.UnitOfWork

 using System;
 using System.Collections.Generic;
 using System.Text;

 namespace Service.ProductService
 {
     public interface IProductService
     {
         string Test();
     }
 }

IProductService

 using Entity.Table;
 using Microsoft.EntityFrameworkCore;

 namespace Service.ProductService
 {
     public class ProductService : IProductService
     {
         private readonly IUnitOfWork _unitOfWork;
         public ProductService(IUnitOfWork unitOfWork)
         {
             _unitOfWork = unitOfWork;
         }

         public string Test()
         {
             var repo = _unitOfWork.GetRepository<Product>();
             repo.Insert(new Product
             {
                 Category = ,
                 Description = "此商品为澳洲代购,买不了吃亏买不了上当",
                 Discount = (decimal)899.21,
                 Price = (decimal)98.2,
                 Name = "澳洲袋鼠粉",
             });
             _unitOfWork.SaveChanges();//提交到数据库
             var result = repo.GetFirstOrDefault()?.Description ?? string.Empty;
             return result;
         }
     }
 }

ProductService

• appsettings.json 的配置

{
  "ConnectionStrings": {
    "MySqlConnection": "Server=localhost;database=ProjectManager;uid=root;pwd=password;"
  },
  "Logging": {
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "AllowedHosts": "*"
}

• Startup 的配置

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<ProductContext>(options =>
                options.UseMySql(Configuration.GetConnectionString("MySqlConnection")));//添加Mysql支持   using Microsoft.EnityFrameworkCore

            services.AddUnitOfWork<ProductContext>();//添加UnitOfWork支持
            services.AddScoped(typeof(IProductService), typeof(ProductService));//用ASP.NET Core自带依赖注入(DI)注入使用的类

            services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
        }

• 有关数据库迁移命令 (注意要选择保护DbContext项目, 视图 -> 其它窗口 ->  程序包管理器控制台)

add-migration init  (注: 初始化)

update-database

add-migration changeProductTable

remove-migration

如果出现找不到表  __efmigrationshistory, 则运行以下SQL

CREATE TABLE `__EFMigrationsHistory` (
  `MigrationId` varchar(95) NOT NULL,
  `ProductVersion` varchar(32) NOT NULL,
  PRIMARY KEY (`MigrationId`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

创建 __EFMigrationsHistory 表