How to specify a property as calculated in Entity Framework?

Question

In examples from Microsoft, they implicitly defined a calculated property by providing only accessor without mutator:

public string NormalProperty { get; set; }
public string CalculatedProperty
{
    get { return "foobar" + NormalProperty; }
}

I also want to have a mutator in CalculatedProperty, which automatically trims the "foobar" suffix and assigns the result back into NormalProperty.

public string CalculatedProperty
{
    get { return "foobar" + NormalProperty; }
    set { NormalProperty = value.Substring(6); }
}

The issue is, Entity Framework now considers CalculatedProperty a normal property, and create a column named "CalculatedProperty" in the database.

I do not want to workaround with this by using functions. Can it be done through Attributes/Fluent API? I am using EF 6.1.

which mode do you use? Code First, or Database first with edmx file? If it is the latter one, I may have a solution — Michael Mairegger, Apr 03 '14 at 08:46
I am building a new website from the ground up using Code First. :( — Livy, Apr 03 '14 at 08:48
possible duplicate of [Ignoring a class property in Entity Framework 4.1 Code First](http://stackoverflow.com/questions/10385248/ignoring-a-class-property-in-entity-framework-4-1-code-first) — Gert Arnold, Apr 03 '14 at 08:50

score 1 · Accepted Answer · answered Apr 03 '14 at 09:41

1

It can be done in your DataContext in code first

protected override void OnModelCreating(DbModelBuilder modelBuilder) 
{
   modelBuilder.Entity<Your_Class>().Ignore(x => x.CalculatedProperty); 
}

answered Apr 03 '14 at 09:41

SWilko

I read Gert Arnold's link above and solved the problem. Thanks for your answer anyway. – Livy Apr 03 '14 at 09:49

1 Answers1