How do you actually perform relationships in Entity Framework 4 Code-First CTP 5? - asp.net

Question

I would like to have a short example on how do you actually perform relationships in Entity Framework 4 Code-First CTP 5 ?
Would love an example for these kind of relations :
* one-to-many
* many-to-many
Thanks a lots!

Answer 1

One to One
public class One
{
public int Id {get;set;}
public virtual Two RelationTwo {get;set;}
}
public class Two
{
public int Id {get;set;}
public virtual One RelationOne {get;set;}
}
Things to note, it has to be virtual
One to Many
public class One
{
public int Id {get;set;}
public virtual ICollection<Two> RelationTwo {get;set;}
}
public class Two
{
public int Id {get;set;}
public virtual One RelationOne {get;set;}
}
Many to Many
public class One
{
public int Id {get;set;}
public virtual ICollection<Two> RelationTwo {get;set;}
}
public class Two
{
public int Id {get;set;}
public virtual ICollection<One> RelationOne {get;set;}
}
note that it needs to be ICollection
Following links maybe helpful, click and click
Hope this helps.
EDIT
Updated to include one to many.
EDIT #2
Updated to include a potential for doing the Invoice <-> Product scenario which was requested by comment.
note: this is untested, but should put you in the right direction
public class Invoice
{
public int Id {get;set;}
//.. etc. other details on invoice, linking to shipping address etc.
public virtual ICollection<InvoiceProduct> Items {get;set;}
}
public class InvoiceProduct
{
public int Id {get;set;}
public int Quantity {get;set;}
public decimal Price {get;set;} // possibly calculated
//.. other details such as discounts maybe
public virtual Product Product {get;set;}
public virtual Invoice Order {get;set;} // maybe but not required
}
public class Product
{
public int Id {get;set;}
//.. other details about product
}
Using this you could then iterate through all the items on the invoice and then foreach be able to show the invoice details about each item as well as a description from the product itself.