c# - List of generic interfaces -

if have generic interface couple of implementing classes such as:

public interface idataelement<t> {     int dataelement { get; set; }     t value { get; set; } }  public class integerdataelement : idataelement<int> {     public int dataelement { get; set; }     public int value { get; set; } }  public class stringdataelement : idataelement<string> {     public int dataelement { get; set; }     public string value { get; set; } } 

is possible pass collection of implementing classes of differing types, without having resort passing object.

it not appear possible define return values as

public idataelement<t>[] getdata() 

or

public idataelement<object>[] getdata()  

any suggestions?

you can declare:

public idataelement<t>[] getdata<t>() 

and

public idataelement<object>[] getdata() 

• although latter isn't you're after (your interface won't variant in c# 4 uses t in both input , output position; if variant, wouldn't able use variance value types). former require caller specify <t>, e.g.

  foo.getdata<string>();

is okay you?

there's no way of expressing "a collection of object, each of implements idataelement<t> different t" unless give nongeneric base class, @ use ilist<idataelement>. in case nongeneric idataelement have dataelement property, leaving value property in generic interface:

public interface idataelement {     int dataelement { get; set; } }  public interface idataelement<t> : idataelement {     t value { get; set; } } 

is useful in particular situation?

it's not clear how you'd want use collection of data elements without knowing types... if above doesn't you, maybe more expected collections.