How do I use Entity Framework 4.0 Inserting event to add items on insert

Question

Supose I have 2 tables

usersTable

• userid guid not null
• username nvarchar
• ...more fields

ArticleTable

• Articleid int not null
• Article ntext
• userid guid not null
• username nvarchar not null
• ...more fields

To add an article, a user has be loged in. So I do this to get their userId and username

 ' get the user currently logged in
        Dim currentUser As MembershipUser = Membership.GetUser()
        ' Determine the currently logged on user's UserId value
        Dim currentUserId As Guid = CType(currentUser.ProviderUserKey, Guid)

What I want is, when an article is inserted into the Article table by the logged in user, I want to add the username and userid to the article table. I am using Entity FrameWork 4.0 and programming in VB thanks yousaid

Answer 1

You can override the SaveChanges method in your object context and then check for the Entities that are in the Insert State. So if you object context is called MembershipEntities and it's auto generated for you, you can create a partial class called MembershipEntities.

In C#...

public partial class MembershipEntities
{
    public override int SaveChanges(SaveOptions options)
    {
        var memberships = this.ObjectStateManager.GetObjectStateEntries(EntityState.Added).Select(e => e.Entity).ToList();

        //Do what you need to do before you insert your data...

        int changes = base.SaveChanges(options);

    }
}

I have not tested this code, but it should work..