List<ImplInterface> ---> IEnumerable<Interface>

[Berryl Hesh]

Converting in the other direction , IEnumerable<Interfaceto
List<ImplInterface>, I can just create a new List<ImplInterface(data)
where data is IEnumerable<Interface>.

How can I convert the List<ImplInterfaceto IEnumerable<Interface>?

Thanks, BH

[Jeroen Mostert]

Berryl Hesh wrote:

Converting in the other direction , IEnumerable<Interfaceto
List<ImplInterface>, I can just create a new List<ImplInterface(data)
where data is IEnumerable<Interface>.

How can I convert the List<ImplInterfaceto IEnumerable<Interface>?

If I understand the question correctly, you have a class ImplInterface that
implements Interface. It's actually unclear to me how you would be able to
convert a generic IEnumerable<Interfaceto a List<ImplInterface>: the
Interface elements in the enumerable don't need to be of type ImplInterface.
Is ImplInterface a wrapper type?

The other way around is more obvious, type-wise. If you have C# 3.0 and .NET
3.5, it's as easy as

aListImplInterface.Cast<Interface>()

If you don't, you can write this method yourself:

static class EnumerableConversion {
static IEnumerable<TCast<T, U>(IEnumerable<Usource) where U : T {
foreach (U u in source) yield return (T) u;
}
}

And call it like so:

EnumerableConversion.Cast<Interface, ImplInterface>(aListImplInterface)

Not half as snappy, obviously.

--
J.

[Berryl Hesh]

aListImplInterface.Cast<Interface>()

Snappy indeed, (once I figured out I need the Linq namespace, that is)

In the meantime I'd figured out that making the List type be List<Interface>
instead of List<ImplInterfacewas just as good here.

Thanks!

"Jeroen Mostert" <jm******@xs4all.nlwrote in message
news:49*********************@news.xs4all.nl...

Berryl Hesh wrote:

>Converting in the other direction , IEnumerable<Interfaceto
List<ImplInterface>, I can just create a new List<ImplInterface(data)
where data is IEnumerable<Interface>.

How can I convert the List<ImplInterfaceto IEnumerable<Interface>?

If I understand the question correctly, you have a class ImplInterface
that implements Interface. It's actually unclear to me how you would be
able to convert a generic IEnumerable<Interfaceto a List<ImplInterface>:
the Interface elements in the enumerable don't need to be of type
ImplInterface. Is ImplInterface a wrapper type?

The other way around is more obvious, type-wise. If you have C# 3.0 and
.NET 3.5, it's as easy as

aListImplInterface.Cast<Interface>()

If you don't, you can write this method yourself:

static class EnumerableConversion {
static IEnumerable<TCast<T, U>(IEnumerable<Usource) where U : T {
foreach (U u in source) yield return (T) u;
}
}

And call it like so:

EnumerableConversion.Cast<Interface, ImplInterface>(aListImplInterface)

Not half as snappy, obviously.

--
J.