EF 4.1 - How to add a default on insertion for datetime column

Question

Using EF 4.1 how could I add a default value to the underlying table? In this particular case how could I set a datetime column to the equivalent of getdate every time I in

Answer 1

You can also modify your T4 template (.tt file) to add a partial method that you call from within the generated constructor. Then, you can create your own partial class and implement the partial method and set your default value.

A snippet from the T4 template where the constructor is created, followed by the partial method. Note the last three lines:

public <#=code.Escape(entity)#>()
{
<#
    foreach (var edmProperty in propertiesWithDefaultValues)
    {
#>
    this.<#=code.Escape(edmProperty)#> = =code.CreateLiteral(edmProperty.DefaultValue)#>;
<#
    }

    foreach (var navigationProperty in collectionNavigationProperties)
    {
#>
    this.<#=code.Escape(navigationProperty)#> = new HashSet<<#=code.Escape(navigationProperty.ToEndMember.GetEntityType())#>>();
<#
    }

    foreach (var complexProperty in complexProperties)
    {
#>
    this.<#=code.Escape(complexProperty)#> = new <#=code.Escape(complexProperty.TypeUsage)#>();
<#
    }
#>

    SetDefaultValues();
}

partial void SetDefaultValues();

That will result in a generated entity having something like:

public Foo()
{
    // Properties set based on defaults in edmx

    SetDefaultValues();
}

partial void SetDefaultValues();

Then, in your partial class, you can simply add something like:

partial void SetDefaultValues()
{
    this.SomeDate = DateTime.Today;
}