How can I pass an array of custom objects through a Web Service?

Here is a brief C# example for passing an array of custom objects through a Web Service. An important point is that the Web service class (CustomObjectArrayWS in the sample code) is decorated with the XmlInclude() attribute, defined in the System.Xml.Serialization namespace.

This is necessary because when you pass an ArrayList into or out of Web services, the SOAP serializer must have access to the metadata (details of methods and properties) for all classes that can be included as elements of the collection. This attribute notifies the serializer to expect elements of the specified type; you can use the attribute many times per attribute target.

<%@WebService Language="c#" class="CustomObjectArrayWS"%>
using System;
using System.Collections;
using System.Web.Services;
using System.Xml.Serialization;
public class CustomObjectArrayWS
{
     	[WebMethodAttribute]
    	[XmlInclude(typeof(Address))]
    	public ArrayList GetAddresses ()
   	{
  		ArrayList al = new ArrayList();
  		Address addr1 = new Address("John Smith", "New York",12345);
  		Address addr2 = new Address("John Stalk", "San Fransisco", 12345);
  			
       		al.Add(addr1);
       		al.Add(addr2);
       		
      		return al;
 	}
} 
// Custom class to be added to the collection to be passed in //and out of the service
public class Address
{
 	public string name;
 	public string city;
 	public int zip; 	
 	// Default ctor needed by XmlSerializer
 	public Address()
 	{
 	}
 	public Address(string _name, string _city, int _zip  )
	{ 
                    this.name = _name;
                    this.city = _city;
                     this.zip = _zip;
           }
       }

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