MySQL-- Entity Framework Code First(EF Code First)

使用MySQL和 Entity Framework Code First(EF Code First)创建数据库。

1、新建控制台项目ConsoleApp1，使用管理NuGet程序，添加MySql.Data.Entities，MySql.Data.Entities（会自动安装依赖项MySql.Data，EntityFramework）

2、安装程序包以后如下：

3、在app.config中添加如下，如果没有app.config，手动创建一个即可。

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <configSections>
        <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
        <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
    </configSections>    
    <connectionStrings>
        <!--添加mysql连接字符串-->
        <add name="conn" connectionString="server=localhost;port=3306;uid=root;pwd=mysql@123456;database=testdb;" providerName="MySql.Data.MySqlClient" />
    </connectionStrings>
    <entityFramework>
        <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
            <parameters>
                <parameter value="v13.0" />
            </parameters>
        </defaultConnectionFactory>
        <providers>
            <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
            <!--添加Asp.Net EF访问Mysql数据库，否则报错：No Entity Framework provider found for the ADO.NET provider with invariant name 'MySql.Data.MySqlClient'.-->
            <provider invariantName="MySql.Data.MySqlClient" type="MySql.Data.MySqlClient.MySqlProviderServices, MySql.Data.Entity.EF6" />
        </providers>
    </entityFramework>
    <system.data>
        <DbProviderFactories>
            <remove invariant="MySql.Data.MySqlClient" />
            <add name="MySQL Data Provider" invariant="MySql.Data.MySqlClient" description=".Net Framework Data Provider for MySQL" type="MySql.Data.MySqlClient.MySqlClientFactory, MySql.Data, Version=6.8.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" />
        </DbProviderFactories>
    </system.data>
    <runtime>
        <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
            <dependentAssembly>
                <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-5.0.0.0" newVersion="5.0.0.0" />
            </dependentAssembly>
            <dependentAssembly>
                <assemblyIdentity name="System.Buffers" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-4.0.3.0" newVersion="4.0.3.0" />
            </dependentAssembly>
            <dependentAssembly>
                <assemblyIdentity name="MySql.Data" publicKeyToken="c5687fc88969c44d" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-6.8.8.0" newVersion="6.8.8.0" />
            </dependentAssembly>
        </assemblyBinding>
    </runtime>
</configuration>

注意：上述红色标记的地方

4、添加数据上下文MyDBContext，代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity;
using System.Text;

namespace ConsoleApp1
{
    public class MyDBContext : DbContext
    {
        public DbSet<Testmy> Testmies { get; set; }
        public MyDBContext(string nameOrConnectionString) : base(nameOrConnectionString)
        {

        }
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Testmy>().ToTable($"tbl-{typeof(Testmy)}")
                .HasKey(a => a.Id)
                .Property(a => a.Id)
                .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
            base.OnModelCreating(modelBuilder);
        }
    }

    public class Testmy
    {
        public int Id { get; set; }
        public string Name { get; set; }

    }
}

5、Program添加如下代码：

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

namespace ConsoleApp1
{
    public class Program
    {
        static void Main(string[] args)
        {
            using (var db = new MyDBContext("name=conn"))
            {
                var isCreate = db.Database.CreateIfNotExists();
                for (int i = 0; i < 10; i++)
                {
                    db.Testmies.Add(new Testmy { Name = $"{i}--名字" });
                }

                db.SaveChanges();
            }
            Console.WriteLine("创建成功");
            Console.Read();
        }
    }
}