Beginning Web Development, Silverlight, and ASP.NET AJAX

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CHAPTER 2 ■ BASICS OF WEB DEVELOPMENT WITH ASP.NET
Figure 2-14. Creating a web reference
Visual Studio will then create a special type of class called a proxy. This is simply a
local representation of the remote service, allowing you to call methods as if they were
implemented on your local computer. However, under the covers, ASP.NET will forward
all of the proxy method calls to the remote service for execution.
If Visual Studio interprets the file successfully, you will see a list of available methods
(GetStockQuotes in the example in Figure 2-14). You can then create a name for the web
reference and add the reference to your project. At this point in your project, you can
create an instance of the web reference proxy class and call the method on it to get data
back from the web service.
In fact, let’s do that now so that we can call a remote web service to obtain stock
quotes for our example. Right-click the project name and select Add Web Reference.
When the Add Web Reference dialog box appears, type http://services.xmethods.net/
soap/urn:xmethods-delayed-quotes.wsdl into the URL field and click Go. We’ll be using a
service provided by XMethods (www.xmethods.com) that reports delayed stock quotes given
a stock ticker symbol. You can see this in Figure 2-14. After clicking Go, Visual Studio contacts
XMethods, downloads the WSDL, and displays the available methods it finds for you
to review. Note the value in the Web reference name field (net.xmethods.services), which
will ultimately form the namespace of the proxy class you’ll be using. Change the value
you find there to “QS” for “quote service,” and then click Add Reference. At this point,