在尝试在我的项目中实现 EF 迁移时,我陷入了困境。
EF Code First MigrateDatabaseToLatestVersion 接受配置中的连接字符串名称。
在我的例子中,数据库名称在运行时已知(用户从下拉列表中选择它)。
正如 DbContext 在其构造函数中接受 ConnectionString 或 connectionString Name 的方式一样,“MigrateDatabaseToLatestVersion”不接受相同的内容
System.Data.Entity.Database.SetInitializer
(new MigrateDatabaseToLatestVersion<SrcDbContext, SRC.DomainModel.ORMapping.Migrations.Configuration>(connString));
还有其他方法可以实现这一目标吗?
谢谢你们。我确实从codeplex上签出了EF代码,并在了解了他们的源代码后继承了我自己的类。这是我选择的解决方案:-
public class MigrateDbToLatestInitializerConnString<TContext, TMigrationsConfiguration> : IDatabaseInitializer<TContext>
where TContext : DbContext
where TMigrationsConfiguration : DbMigrationsConfiguration<TContext>, new()
{
private readonly DbMigrationsConfiguration config;
/// <summary>
/// Initializes a new instance of the MigrateDatabaseToLatestVersion class.
/// </summary>
public MigrateDbToLatestInitializerConnString()
{
config = new TMigrationsConfiguration();
}
/// <summary>
/// Initializes a new instance of the MigrateDatabaseToLatestVersion class that will
/// use a specific connection string from the configuration file to connect to
/// the database to perform the migration.
/// </summary>
/// <param name="connectionString"> connection string to use for migration. </param>
public MigrateDbToLatestInitializerConnString(string connectionString)
{
config = new TMigrationsConfiguration
{
TargetDatabase = new DbConnectionInfo(connectionString, "System.Data.SqlClient")
};
}
public void InitializeDatabase(TContext context)
{
if (context == null)
{
throw new ArgumentException("Context passed to InitializeDatabase can not be null");
}
var migrator = new DbMigrator(config);
migrator.Update();
}
}
public static class DatabaseHelper
{
/// <summary>
/// This method will create data base for given parameters supplied by caller.
/// </summary>
/// <param name="serverName">Name of the server where database has to be created</param>
/// <param name="databaseName">Name of database</param>
/// <param name="userName">SQL user name</param>
/// <param name="password">SQL password</param>
/// <returns>void</returns>
public static bool CreateDb(string serverName, string databaseName, string userName, string password)
{
bool integratedSecurity = !(!string.IsNullOrEmpty(userName) || !string.IsNullOrEmpty(password));
var builder = new System.Data.SqlClient.SqlConnectionStringBuilder
{
DataSource = serverName,
UserID = userName,
Password = password,
InitialCatalog = databaseName,
IntegratedSecurity = integratedSecurity,
};
var db = new SrcDbContext(builder.ConnectionString);
var dbInitializer = new MigrateDbToLatestInitializerConnString<SrcDbContext, SRC.DomainModel.ORMapping.Migrations.Configuration>(builder.ConnectionString);
//following uses strategy to "CreateIfNotExist<>"
dbInitializer.InitializeDatabase(db);
return true;
}
}
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系:hwhale#tublm.com(使用前将#替换为@)