Beginning Web Development, Silverlight, and ASP.NET AJAX

CHAPTER 5 ■ ASP.NET WEB SERVICES 109
This isn’t always the case when you use technologies other than ASP.NET, where you may
end up with differences between your service code and its description.
You can see what the default ASMX file markup looks like here:
It’s pretty straightforward and might seem like little more than a file that describes
the language of the code-behind file, the location of the code-behind file, and the main
class that implements your service. However, note the . These denote
an ASP.NET directive and tell ASP.NET to get ready to work its magic. The WebService is the
directive itself, and in this case you’re telling ASP.NET to fire up its web service–processing
infrastructure (if you look back to Listing 3-3, you’ll see another ASP.NET directive, Page,
which tells ASP.NET to generate a web page).
The code-behind file is where the action happens in your web service. You can see
the default example in Listing 5-1.
Listing 5-1. Default Web Service
using System;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
public class Service : System.Web.Services.WebService
{
public Service () {
}
//Uncomment the following line if using designed components
//InitializeComponent();
[WebMethod]
public string HelloWorld() {
return "Hello World";
}
}