domain driven design - How can I get a property as an Entity in Action of Asp.Net Mvc? -

i'd know how can property entity, example:

my model:

public class product {     public int id { get; set; }    public string name { get; set; }    public category category { get; set; }  } 

view:

name: <%=html.textboxfor(x => x.name) %> category: <%= html.dropdownlist("category", ienumerable<selectlistitem>)viewdata["categories"]) %> 

controller:

public actionresult save(product product) {    /// produtct.category ??? } 

and how category property ? it's fill view ? asp.net mvc know how fill object id ?

thanks!

this 1 of reasons why it's bad bind directly entities. consider

public class productform {    public int id { get; set; }    public string name { get; set; }    public string categoryid { get; set; } }  public actionresult save(productform form) {    var product = new product    {         id = form.id,         name = form.name,         category = database.getcategory(form.categoryid)    }; } 

in case of view models above, may ok use custom model binders automatically entities id database. see here sample implementation (in s#arp architecture) binds ids entities database. think better go simpler implementation above.

you can use automapper simplify form->entity mapping.