Mapping .NET types to a database using the Fluent API

Question

I'm using the CultureInfo class to describe the language of localizable data in my application.

class LocalizedText
{
    public int Id { get; set; }

    public string Text { get; set; }

    public CultureInfo Language { get; set; }
}

Now I'd like to map the above class to a database table, using a code first approach.

Sample data:

 +----+------------------------+----------+
 | Id | Text                   | Language |
 +----+------------------------+----------+
 |  1 | Hello World!           | en       |
 +----+------------------------+----------+
 |  1 | Hallo Welt!            | de       |
 +----+------------------------+----------+
 |  1 | Bonjour tout le monde! | fr       |
 +----+------------------------+----------+

I thought this would be easy enough to do using the Fluent API in EF6, but I guess it's not.

What I've tried:

modelBuilder.Entity<CultureInfo>()
            .HasKey(info => info.TwoLetterISOLanguageName);

But then I get an error. Presumably because CultureInfo.TwoLetterISOLanguageName is read-only.

The key component 'TwoLetterISOLanguageName' is not a declared property on type 'CultureInfo'. Verify that it has not been explicitly excluded from the model and that it is a valid primitive property.

So can this be done at all?

Answer 1

You cannot map CultureInfo class to column in database. But you can ignore this property and create another string property which will be mapped:

modelBuilder.Entity<LocalizedText>()
    .Ignore(lt => lt.Language);

modelBuilder.Entity<LocalizedText>()
    .Property(lt => lt.TwoLetterISOLanguageName)
    .HasColumnName("Language");

And then just set Language property when TwoLetterISOLanguageName is assigned:

public class LocalizedText
{
    public int Id { get; set; }
    public string Text { get; set; }
    public CultureInfo Language { get; set; }

    public string TwoLetterISOLanguageName
    {
      get { return Language == null ? null : Language.TwoLetterISOLanguageName; }
      set { Language = CultureInfo.GetCultureInfo(value); }
    }
}