Как создать пользовательский ReusableDbContext

Question

Три класса:

• CustomDbContext
• ReusableContext
• DbContext

Связь:

• ReusableContext: DbContext
• CustomDbContext: ReusableContext

Код:

public class ReusableDbContext : DbContext
{
    public ReusableDbContext() 
        : base("name = myConnectionString")
    {
        Database.SetInitializer＜ReusableDbContext＞(new 
MigrateDatabaseToLatestVersion＜ReusableDbContext, ReusableMigrationsConfiguration＞());
    }

    public DbSet＜ReusableTable＞ ReusableTables{ get; set; }
}

public class ReusableMigrationsConfiguration : DbMigrationsConfiguration＜ReusableDbContext＞
{
    public ReusableMigrationsConfiguration()
        : base()
    {
        AutomaticMigrationsEnabled = true;
        AutomaticMigrationDataLossAllowed = true;
    }

    protected override void Seed(ReusableDbContext context)
    {
        //ReusableMigrationsConfiguration Seed Logic here
        // this Seed method is never called  -----------  The Problem here!
    }
}

затем я пытаюсь использовать ReusableContext следующим образом:

public class CustomDbContext : ReusableDbContext
{
    public CustomDbContext() 
        : base()
    {
        Database.SetInitializer＜CustomDbContext＞(new 
MigrateDatabaseToLatestVersion＜CustomDbContext, CustomMigrationsConfiguration＞());
    }

    public DbSet＜CustomTable＞ CustomTables{ get; set; }
}

public class CustomMigrationsConfiguration : DbMigrationsConfiguration＜CustomDbContext＞
{
    public CustomMigrationsConfiguration()
        : base()
    {
        AutomaticMigrationsEnabled = true;
        AutomaticMigrationDataLossAllowed = true;
    }

    protected override void Seed(CustomDbContext context)
    {
        //CustomMigrationsConfiguration Seed Logic
        // this Seed method is called, no problem here
    }
}

после запуска проекта:

• ReusableTable и CustomTable созданы
• Вызывается метод Seed для CustomMigrationsConfiguration, и ОК
• НО, метод Seed метода ReusableMigrationsConfiguration НЕ вызывается -------- Что не так?

Answer 1

Проблема решена, вот решение.

Класс:

• CustomDbContext, CustomMigrationsConfiguration
• ReusableContext, ReusableMigrationsConfiguration ＜ TContext ＞
• DbContext

Отношение:

• ReusableContext: DbContext
• ReusableMigrationsConfiguration ＜ TContext ＞: DbMigrationsConfiguration ＜ TContext ＞ где TContext: ReusableContext
• CustomMigrationsConfiguration: ReusableMigrationsConfiguration ＜ CustomDbContext ＞

Код:

public class ReusableDbContext : DbContext
{
    public ReusableDbContext() 
        : base("name = myConnectionString")
    {
        Database.SetInitializer＜ReusableDbContext＞(new 
MigrateDatabaseToLatestVersion＜ReusableDbContext, ReusableMigrationsConfiguration＞());
    }

    public DbSet＜ReusableTable＞ ReusableTables{ get; set; }
}

public class ReusableMigrationsConfiguration＜TContext＞ : DbMigrationsConfiguration＜TContext＞ where TContext : ReusableDbContext
{
    public ReusableMigrationsConfiguration()
        : base()
    {
        AutomaticMigrationsEnabled = true;
        AutomaticMigrationDataLossAllowed = true;
    }

    protected override void Seed(TContext context)
    {
        //ReusableMigrationsConfiguration Seed Logic here
        // is called and OK now.
    }
}

Теперь мы можем повторно использовать ReusableContext следующим образом:

public class CustomDbContext : ReusableDbContext
{
    public CustomDbContext() 
        : base()
    {
        Database.SetInitializer＜CustomDbContext＞(new 
MigrateDatabaseToLatestVersion＜CustomDbContext, CustomMigrationsConfiguration＞());
    }

    public DbSet＜CustomTable＞ CustomTables{ get; set; }
}

public class CustomMigrationsConfiguration : ReusableMigrationsConfiguration＜CustomDbContext＞
{
    public CustomMigrationsConfiguration()
        : base()
    {
        AutomaticMigrationsEnabled = true;
        AutomaticMigrationDataLossAllowed = true;
    }

    protected override void Seed(CustomDbContext context)
    {
        base.Seed(context);



        //CustomMigrationsConfiguration Seed Logic
        // this Seed method is called and OK
    }
}

после запуска проекта:

• Создаются ReusableTable и CustomTable;
• Вызывается метод Seed для CustomMigrationsConfiguration и OK;
• Вызывается метод Seed для ReusableMigrationsConfiguration и OKтоже.

сейчас все вроде бы нормально:)

Answer 2

public class CustomDbContext : **ReusableDbContext**
{
    public CustomDbContext() 
        : base()
    {
        Database.SetInitializer＜CustomDbContext＞(new 
MigrateDatabaseToLatestVersion＜CustomDbContext, CustomMigrationsConfiguration＞());
    }

    public DbSet＜CustomTable＞ CustomTables{ get; set; }
}

Сделай это будет работать

public class CustomMigrationsConfiguration : DbMigrationsConfiguration＜CustomDbContext＞
{
    public ReusableMigrationsConfiguration()
        : base()
    {
        AutomaticMigrationsEnabled = true;
        AutomaticMigrationDataLossAllowed = true;
    }

    protected override void Seed(CustomDbContext context)
    {
        //CustomMigrationsConfiguration Seed Logic
        // this Seed method is called, no problem here
    }
}