Complex Data Type

BSkelding · May 12th, 2005, 12:40 PM

Is there a way to allow Web Services to accept complex data types such as Arraylists, hashtables, and user defined types? Likewise, is it possible for them to return these types as a result?

Thanks in advance.
Brian

planoie · May 12th, 2005, 12:54 PM

It most certainly is possible. When you have a web method that accepts or returns a complex type the WSDL that get generated has definitions for those types. When you set up a web reference to that web service, the proxy class file will have stub classes (built off the WSDL) that outline your complex types (even those you define). When you call the web service methods via the proxy class you interact with them in the same way you would interact with the actual methods of the actual web service class.

-Peter

BSkelding · May 12th, 2005, 01:44 PM

I'm still pretty new to this whole web service thing. I only grasped part of what you stated in your post.

All I know is that if I create a web service called "Test" with the following signature:

<WebService()> Public Function Test(byval x as arraylist, byval y as object) as Hashtable

I end up recieving the following message - The type Systems.Collection.Hashtable is not supported because it implements IDictionary.

planoie · May 12th, 2005, 01:56 PM

Do you mean "<WebMethod()>"?

I just created a new web service with a method like this:

<WebMethod()> Public Function Test(ByVal x As ArrayList, ByVal y As Object) As Hashtable

And it compiled fine.

-Peter

jacob · May 12th, 2005, 02:15 PM

I am also pretty new to all this web service stuff, and also new to the remoting world, at least in C# and .NET. However I think I managed to serialize a Hashtable the other day... Here is the code

Code:

    [Serializable]
    public class Hasher : Hashtable, ISerializable 
    {
        public Hasher()
        {

        }

        public Hasher(SerializationInfo info, StreamingContext context)
        {
            SerializationInfoEnumerator i = info.GetEnumerator();
            while(i.MoveNext())
                this.Add(i.Name, i.Value);
        }

        void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
        {
            IDictionaryEnumerator i = this.GetEnumerator();
            while(i.MoveNext())
                info.AddValue((string)i.Key, i.Value);
        }        
    }

I may be worng, so please correct me if this is not the right way to do it.

Hope it helps, Jacob.

BSkelding · May 12th, 2005, 02:30 PM

Oooppss...yes I meant <WebMethod()> The Webservice itself will compile fine it's when I try to update the web reference in the application (an ASP.NET app) that I get the error. Thoughts????