UWP SQL Server迁移不起作用

Question

I installed the latest version of Windows 10 (fall creators update) and Visual Studio 2017 (15.4).

I created an UWP app targeted to major version and installed by Nuget:

• microsoft.entityframeworkcore.tools
• microsoft.entityframeworkcore.sqlserver

This is my code:

[Table("tbProva")]
public class Prova
{
    public Prova()
    {
        Indirizzi = new List<Indirizzo>();
    }

    [Key]
    public Guid Id { get; set; }

    [MaxLength(250)]
    public string Nome { get; set; }
    public ICollection<Indirizzo> Indirizzi { get; set; }
}

public class ProvaConfig : IEntityTypeConfiguration<Prova>
{
    public void Configure(EntityTypeBuilder<Prova> builder)
    {
        builder.HasMany(c => c.Indirizzi)
            .WithOne(c => c.Prova)
            .HasForeignKey(c => c.IdProva)
            .OnDelete(DeleteBehavior.Cascade);
    }
}

[Table("tbIndirizzi")]
public class Indirizzo
{
    [Key]
    public Guid Id { get; set; }
    [MaxLength(250)]
    public string Strada { get; set; }
    [MaxLength(10)]
    public string Civico { get; set; }
    public Prova Prova { get; set; }
    public Guid IdProva { get; set; }
}

public class DcContext : DbContext
{
    public DbSet<Prova> tbProva { get; set; }
    public DbSet<Indirizzo> tbIndirizzi { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        optionsBuilder.UseSqlServer("Server=Europa;Database=ProvaDb;Trusted_Connection=True;");
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.ApplyConfiguration<Prova>(new ProvaConfig());
    }
}

If I run migration, I get this result:

PM> Add-Migration poi 

System.TypeLoadException: Non è stato possibile caricare il tipo 'System.Globalization.CultureInfo' dall'assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

If I remove the navigation properties from model and I do not override OnModelCreating , it works fine.

Thanks

Answer 1

Ensure that the System.Globalization NuGet packge is installed and up-to-date.

Also, if you are going to use EntityFramework please make sure that you installed the microsoft.entityframeworkcore package is installed too.

Answer 2

This should be a known issue,see issue #9666 .

While testing EF Core 2.0 with .NET UWP 6.0 we found that there are new types that present similar problems. Eg: System.TypeLoadException: Could not load type 'System.Globalization.CultureInfo' from assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. System.TypeLoadException: Could not load type 'System.MarshalByRefObject' from assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

One example of above exception was DataAnnotations . And in your code snippet just referenced the System.ComponentModel.DataAnnotations namespace.

And it seems like this patch bug is approved for the 2.0.x patch. See issue #9827 .