使用Entity Framework 6和一个有效的PostgreSQL数据库加连接，我试图运行Add-Migration和Update-Database命令并通过控制台应用程序创建更新脚本。可以从控制台运行命令，因为它“只是API的精简包装”，请参阅我使用的示例this SO-answer。
创建迁移工作，创建了三个常规文件，即：
Initial.cs
Initial.Designer.cs
Initial.resx
以下是适用于Update-Database的控制台应用。
public static void Main()
{
// Specify the name of the database migration
// Note: make sure to create a new name for each new migration and prefix with
const string MIGRATION_NAME = "Initial";
// END USER INPUT
// Get executing path from which the location of the Update_Scripts and new
// Migrations can be determined.
var executingPath = AppDomain.CurrentDomain.BaseDirectory;
// Write to database (PowerShell: Update-Database)
var config = new Configuration();
var migrator = new DbMigrator(config);
migrator.Update(); // <= HERE IT CRASHES!
// Now create the PostgreSQL update script.
var scriptor = new MigratorScriptingDecorator (migrator);
string script = scriptor.ScriptUpdate (sourceMigration: null, targetMigration: null);
var updateScriptPath = Regex.Replace (executingPath, "Zk.Migrations/.*",
"Zk/App_Data/Update_Scripts");
File.WriteAllText (updateScriptPath + MIGRATION_NAME + ".postgresql", script);
Console.WriteLine ("Update script {0} written to App_Data/Update_Scripts folder", MIGRATION_NAME);
}
此处Configuration类如下所示：
public class Configuration : DbMigrationsConfiguration<ZkContext>
{
public Configuration ()
{
AutomaticMigrationsEnabled = false;
SetSqlGenerator("Npgsql", new PostgreSqlMigrationSqlGenerator());
}
}
PostgreSqlMigrationSqlGenerator班级来自this GitHub repository。
当我尝试运行控制台应用程序上方的更新数据库部分时migrator.Update();崩溃了。这是例外：
无法找到适合指定文化或中性文化的任何资源。确保在编译时将“Zk.Migrations.Initial.resources”正确嵌入或链接到程序集“Zk.Migrations”中，或者所有所需的附属程序集都是可加载和完全签名的。
这是堆栈跟踪：
System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists（mustSucceedToKeepDatabase =
{System.Action}）in System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists
（mustSucceedToKeepDatabase = {System.Action}）in
System.Data.Entity.Migrations.DbMigrator.Update（targetMigration =（null））in
System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update（）in /home/erwin/zaaikalender/Zk.Migrations中的Zk.Migrations.MigrationsTool.Main（）/MigrationsTool.cs:78
我不知道如何提供正确的资源并让脚本工作。我应该首先运行Enable-Migrations，如果是，如何运行？我希望有人可以帮助我！感谢。
答案 0 :(得分：0)
要使控制台应用程序能够添加代码优先迁移，创建脚本和更新数据库，需要做两件事：
.cs.，.resx和.Designer.cs文件，其名称与迁移脚手架名称相同，但不迁移MigrationId preprended。否则无法找到文件。.resx文件并选择BuildAction＆＃34; EmbeddedResource＆＃34;否则无法找到资源。控制台应用的完整工作脚本（使用PostgreSqlMigrationSqlGenerator）：
/// <summary>
/// Class used to generate the code migrations and SQL script based on the Models and update the database.
/// (I.e., runs PowerShell's Add-Migration and Update-Database, and creates a PostgreSQL script.)
/// See: http://stackoverflow.com/questions/20374783/enable-entity-framework-migrations-in-mono#20382226
///
/// Usage: run by setting Zk.Migrations as Startup project and pressing play.
///
/// Classes of namespace EntityFramework.PostgreSql obtained from:
/// https://github.com/darionato/PostgreSqlMigrationSqlGenerator. License is included.
/// </summary>
class MigrationsTool
{
/// <summary>
/// The entry point of the program, where the program control starts and ends.
/// </summary>
public static void Main()
{
// USER INPUT /////////////////////////////////////////////////////////////////////////////////
// Always first create a new database migration with DatabaseStep.ADD_MIGRATION,
// and include the created files in the project and set resource file to EmbeddedResource.
// After creating a migration run UPDATE_DATABASE to update the database.
const DatabaseStep step = DatabaseStep.UPDATE_DATABASE;
// Specify the name of the database migration in case of ADD-MIGRATION.
// Note: Make sure to create a new name for each new migration.
// After creating migration include the files in the folder by right clicking on
// Zk.Migrations and selecting "Add files from folder". Then add the .cs, .resx and
// .Designer.cs files with the name specified below.
// Last but not least set the .resx file's build action to EmbeddedResource by right
// clicking on it.
// Make sure that the Setup.postgresql script has run manually to create the database user.
const string MIGRATION_NAME = "CalendarAndUser";
// END USER INPUT /////////////////////////////////////////////////////////////////////////////
// Get executing path from which the location of the Update_Scripts and new Migrations can be determined.
var executingPath = AppDomain.CurrentDomain.BaseDirectory;
// Add a new migration (PowerShell: Add-Migration)
if (step == DatabaseStep.ADD_MIGRATION) {
// Initialize the wrapper classes around the Entity Framework PowerShell API.
var config = new Configuration();
var scaffolder = new MigrationScaffolder(config);
var migration = scaffolder.Scaffold(MIGRATION_NAME);
// Place migration code in main project "Migrations" folder and migration scripts in "App_Data"
var migrationsPath = Regex.Replace(executingPath, "bin/.*", "");
// Write migrations
File.WriteAllText (migrationsPath + MIGRATION_NAME + ".cs", migration.UserCode);
File.WriteAllText (migrationsPath + MIGRATION_NAME + ".Designer.cs", migration.DesignerCode);
using (var writer = new ResXResourceWriter (migrationsPath + MIGRATION_NAME + ".resx"))
{
foreach (var resource in migration.Resources)
{
writer.AddResource(resource.Key, resource.Value);
}
}
Console.WriteLine("EF code migration {0} written to Migrations folder...\n\n" +
"Next step is to include the .cs, .resx and .Designer.cs file in the project" +
"by right clicking on the project and selecting " +
"\"Add files from folder.\"\n" +
"Then right click on {0}.resx and set build action to \"EmbeddedResource\""
, migration.MigrationId);
}
else if (step == DatabaseStep.CREATE_SCRIPT)
{
var config = new Configuration();
var migrator = new DbMigrator(config);
var scriptor = new MigratorScriptingDecorator(migrator);
// Determine name of the previous run migration if exists.
string lastMigration = migrator.GetDatabaseMigrations().LastOrDefault();
// Get the script
string script = scriptor.ScriptUpdate(sourceMigration: lastMigration, targetMigration: MIGRATION_NAME);
// Create the PostgreSQL update script based on last migration on database and
// current migration.
string formattedScript = string.Format
("/* * * * * * * * * * * * * * * * * * * * * * *\n" +
" *\n" +
" * Migration:\t\t{0}\n *\n" +
" * Date and time:\t{1}\n" +
" *\n" +
" * * * * * * * * * * * * * * * * * * * * * * */\n\n" +
"{2}",
MIGRATION_NAME,
DateTime.Now,
script);
// Write string to file in Migrations folder of main project
var updateScriptPath = Regex.Replace(executingPath, "Zk.Migrations/.*", "Zk/App_Data/Migrations/");
File.WriteAllText(updateScriptPath + MIGRATION_NAME + ".postgresql", formattedScript);
Console.WriteLine("Update script {0}.postgresql written to Zk/App_Data/Migrations folder.\n" +
"Please include the script by right clicking on the folder and selecting " +
"\"Add files to folder\"," +
"\nIt is recommended to prefix the filename with the current datetime.",
MIGRATION_NAME);
}
// If a new migration is created the database can be updated. (PowerShell: Update-Database)
else if (step == DatabaseStep.UPDATE_DATABASE)
{
var config = new Configuration();
var migrator = new DbMigrator(config);
// Write to database
migrator.Update();
// Show which migrations were applied.
var migrationNames = string.Join(", ", migrator.GetDatabaseMigrations().ToArray().First());
Console.WriteLine("Applied migration {0} to database.", migrationNames);
}
}
/// <summary>
/// Enumeration for specifying the step in the migration.
/// </summary>
private enum DatabaseStep
{
ADD_MIGRATION,
CREATE_SCRIPT,
UPDATE_DATABASE
}
}