Pavel
Tue Jul 15 07:30:21 CDT 2008
On Jul 15, 12:40=A0pm, "Pieter" <pieterNOSPAMcou...@hotmail.com> wrote:
> Hi,
>
> A little bit linked to my other question: I thought it was possible to ha=
ve
> generic list which accept multiple types of objects. So a statement as ""=
Dim
> MyList as List(Of clsClass1, clsClass2)" would accept instances of both
> clsClass1 and clsClass2.
>
> But, it doesn't work :-) Am I simply wrong, or did I do something wrong?
If you want a list of related objects, then it is likely that they
should have a common base class (or implement some common interface).
If you _really_ want a typesafe list of unrelated objects (for
example, because ordering is relevant), then you can use the
Either<T1, T2> type from ECMA TR/89 (
http://www.ecma-international.org/
publications/techreports/E-TR-089.htm):
var list =3D new List<Either<Class1, Class2>>();
list.Add(new Class1());
list.Add(new Class2());
foreach (var item in list)
{
if (item.IsFirst)
{
Class1 c1 =3D (Class1)item;
...
}
else if (item.IsSecond)
{
Class2 c2 =3D (Class2)item;
...
}
}
By the way, please do not use "cls" prefix for your classes - this is
against pretty much all naming conventions in the .NET land. Class
names are supposed to begin with a capital letter, and Hungarian
notation is generally frowned upon, but particularly so for type names.