yes you can do it..
here the sample:
public class Service1 : System.Web.Services.WebService
{
[WebMethod]
public person GetPerson()
{
return new person() {username ="some" , address ="add",age = 25 };
}
[WebMethod]
public void passPersonToDosomeAction(person p)
{
string addres = p.address;
}
}
public class person
{
public string username { get; set; }
public int age { get; set; }
public string address { get; set; }
}