Question

I want to write a custom class extension. I have EDMX class but I want to parse to CUSTOM class. For example Customer Class has 3 properties (id, name, surname) on the other hand my Custom Customer Class has 3 properties (id, name, surname). I want to parse List<Customer> to List<MyCustomer> with using an extension but how can I do that?

public partial class MyVisitorAdvertisement
{
    public int ID { get; set;}
    public int VID { get; set;}
    public int TID { get; set;}
    public string Detail{ get; set;}
    public DateTime Date { get; set;}
    public DateTime LastDate { get; set;}

    public MyVisitorAdvertisement()
    {
    //constructor
    }

    public List<MyVisitorAdvertisement> ListByID( int ID)
{
    List<MyVisitorAdvertisement> visitors = new List<MyVisitorAdvertisement>();
    using (var Ctx = new DomainRepository<VisitorAdvertisement>(new ProposalsEntities()))
    {
        foreach (var visitor in Ctx.Find<VisitorAdvertisement>(q => q.ID == ID).ToList())
        {
            MyVisitorAdvertisement visitoradvertisement = new MyVisitorAdvertisement();
            visitoradvertisement.ID = visitor.ID;
            // i dislike to do it. i think that how to make it a extention?    

            visitors.Add(visitoradvertisement);
        }
        return visitors;
    }
}
}

My desired extension:

public static List<TResult> (this IEnumerable<T> mylist) where TResult,T: class
{
  return //mylist parse to List<TResult>
}

Answer 1

Something like:

public static List<TResult> ListByID<TResult>(this IEnumerable<T> mylist) where TResult : VisitorAdvertisement where T: class
{
   return Ctx.Find<TResult>(q => q.ID == ID).SelectMany(a => new TResult{ Id = a.Id}).ToList();
}

If VisitorAdvertisement inherited from a base entity that had the ID in it then you could base the resriction on that instead opening up to anything derived from it. Sorry I keep get the syntax wrong, I’m not coding this in VS.Net