How do I map a char property using the Entity Framework 4.1 "code only" fluent API?

user_75701 0
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I have an object that has a char property:

public class Product
{
    public char Code
    {
        get;
        set;
    }
}

Entity Framework doesn't seem to be able to map chars (this field is missing from the database when I create the database schema from my model objects). Is there anyway I can map the char (e.g. to a string) using the fluent API? I don't want to change the model objects as they are part of a legacy shared library.

ef4-code-only fluent-interface char entity-framework
5 Answers

[Column( TypeName = "char(1)" )]

works for me with EF core 3.1.4

user_126918490

I have tried all the ways I have imagined and I must say the the accepted answer is the unique way to solve the problem of the char type as far as I know.

The char type isn't available for its use in EntityFramework.

Fluent API is included in this restriction.

If you try to put a char on the Property(p => p.MyCharProperty) will give you an Exception.

That means that char properties aren't available for Fluent API nor Attributes.

The easiest solution is this (as proposed by Ladislav Mrnka).

public class Product
{
    public char Code { get; set; }

    [Column("Code", TypeName="char")]
    [MaxLength(1)]
    public string CodeString
    {
         get { return Code.ToString(); }
         set { Code = value[0]; }
    }
}

One note: you can't put the property private, protected or internal. Must be public.

Fluent API version would be like this.

public class Product
{
    public char Code { get; set; }

    //We need the property but we will use the Fluent API to replace the attributes
    public string CodeString
    {
         get { return Code.ToString(); }
         set { Code = value[0]; }
    }
}

modelBuilder.Entity<Product>().Property(p => p.Code)
    .HasTypeName("char")
    .HasMaxLength(1)
user_111971150

There is alternate ways to tackle this issue for TESTING purpose only. Make the field not null to null able for time being from design mode. Sometime it is restricted SQL Management Studio. (Change setting Tools -> Option ->Designer -> Table Database designer -> Uncheck "Prevent saving changes that required table creation"

user_28202000
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