可以在实体框架中创建一个类似于Fluent NHibernate中的映射类吗？

Question

I want to create a mapping class similar to the one mentioned below. I want to convert this Fluent NHibernate mapping class to Entity Framework.

Fluent NHibernate

using FluentNHibernate.Mapping;

using MyBlog.Core.Objects;


public class PostMap: ClassMap<Post>
{
    public PostMap()
    {
        Id(x => x.Id);

        Map(x => x.Title)
            .Length(500)
            .Not.Nullable();

        Map(x => x.ShortDescription)
            .Length(5000)
            .Not.Nullable();

        Map(x => x.Description)
            .Length(5000)
            .Not.Nullable();

        Map(x => x.Meta)
            .Length(1000)
            .Not.Nullable();

        Map(x => x.UrlSlug)
            .Length(200)
            .Not.Nullable();

        Map(x => x.Published)
            .Not.Nullable();

        Map(x => x.PostedOn)
            .Not.Nullable();

        Map(x => x.Modified);

        References(x => x.Category)
            .Column("Category")
            .Not.Nullable();

        HasManyToMany(x => x.Tags)
            .Table("PostTagMap");
    }
}

Is NHibernate support available with Hosting Services? Is it easily available with any ASP.NET Hosting or only selected services use it?

Answer 1

Yes, Entity Framework has the similar mappings.

NHibernate:

public PostMap()
{
    Map(x => x.Title)
        .Length(500)
        .Not.Nullable();
}

Entity Framework:

public class YourDomainModelContext : DbContext
{
    public YourDomainModelContext() { }
    ...
    public DbSet<Post> Posts { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
        modelBuilder.Entity<Post>()
            .Property(u => u.Title)
            .HasMaxLength(500);
    }
}

You can get more information in these blog-posts:

• Configuring/Mapping Properties and Types with the Fluent API
• Entity Framework Mapping Scenarios
• Fluent API vs Data Annotations

Answer 2

For EF4 and EF5 there are Fluent API generators, but for EF6 not. I'm also searching for one that works.