有時需要在網上租用空間或數據庫,Mysql成本低一些,所以想將sql server轉成mysql……
注意:在安裝Mysql時要選擇文字集為utf8,否則將不能使用中文(當前也可以在創建數據庫時使用utf8,不過我不知道在ef生成數據庫時如何設置,希望高手指點)
一、在項目中引用mysql的EF包
通過NuGet包管理器安裝:EntityFramework6.1.3、MySql.Data.Entity6.9.8
也可以用nuget的命令行加入:
Install-Package MySql.Data.Entity
二、新建相關類
1、新建 User 實體類
并定義實例的字段長度,不定義的話會出現Specified key was too long;max key length is 767 bytes 的錯誤,這是因為string 類型直接映射到mysql 中的話是longtext,而mysql 支持最大長度為767 bytes.
| public class User{public int Id { get; set; }[StringLength(30)]public string UserName { get; set; }[MaxLength(30)]public string PassWord { get; set; } } |
2、新建 MyContext 類
并說明用MySql進行實現 [DbConfigurationType(typeof(MySqlEFConfiguration))]
| [DbConfigurationType(typeof(MySqlEFConfiguration))]public class MyContext : DbContext{public MyContext(): base("name=MyContext")//web.config中connectionstring的名字{}public DbSet<User> Users { get; set; }} |
3、寫測試代碼
| Database.SetInitializer(new DropCreateDatabaseIfModelChanges<MyContext>());var context = new MyContext();//插入一行值context.Users.Add(new User { UserName = "EF6MySQL" });context.SaveChanges(); |
三、配置Web.config
在<connectionStrings>中加入以下代碼:
| <add name="MyContext" connectionString="Data Source=localhost;port=3306;Initial Catalog=MySQL_EF;user id=root;password=root;" providerName="MySql.Data.MySqlClient" /> |
完整的web.config如下:
| <?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><entityFramework><defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory , EntityFramework" /><providers><provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" /><provider invariantName="MySql.Data.MySqlClient" type="MySql.Data.MySqlClient.MySqlProviderServices, MySql.Data.Entity.EF6, Version=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d"></provider></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=6.9.8.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" /></DbProviderFactories></system.data><connectionStrings><add name="MyContext" connectionString="Data Source=localhost;port=3306;Initial Catalog=MySQL_EF;user id=root;password=root;" providerName="MySql.Data.MySqlClient" /></connectionStrings></configuration> |