Re: problems returning ArrayList from webServices

From: Mickey Williams (my)
Date: 04/13/04 

Date: Tue, 13 Apr 2004 09:24:04 -0700

You have two problems:
 - Collections are always serialized as simple arrays.
 - The general-purpose collection classes in the framework are only typed to
work with object.

If you return an instance of a type that will cause other types to be
serialized polymorphically, you must use SoapInclude or XmlInclude
attributes to include the proper runtime type information.

If you want to serialize as a specific collection class rather than just an
array, wrap it. So if you had a class called Boat, and a strongly-typed
collection called BoatCollection, define your web method like:

[WebMethod]
public BoatRet GetBoats()
{
          BoatRet ret = new BoatRet();
          ret.Boats.Add(...);
          ret.Boats.Add(...);
          ret.Boats.Add(...);
          return ret;
}

class BoatRet
{
          BoatCollection _boats = new BoatCollection();
          public BoatCollection Boats
          {
                 get { return _boats; }
          }
} 

-- 
Mickey Williams
Author, "Microsoft Visual C# .NET Core Reference", MS Press
www.servergeek.com
"Mario Rodriguez" <mrodriguez@avantica.net> wrote in message
news:eaEbN9MIEHA.2144@TK2MSFTNGP12.phx.gbl...
> Hi, I'm in a big problem because my implementation of a webService that
> returns an ArrayList object have a weird behaviour.  On the client side,
> instead of return an ArrayList object, returns an object[] !!!!.  This is
> normal or correct ????????
>
> My other problem is that the ArrayList (and object[]) contains references
to
> an object My Container, that is out the namespace of the webService (so
I've
> to add the reference to MyContainer in both the client side and the
> webService) but on the client side, when I try read the objects from the
> object[] I got a castException due to the objectArray contains instances
of
> webService.namespace.MyContainer and not of
> myContainer.namespace.MyContainer.
>
> I'm not sure what is happening in both situations, that if someone can
give
> me a helping hand, I'll thank you a lot
>
>

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