Once a Silverlight application has a service reference to an ASMX web service, it can invoke the web service through a proxy object. The basic steps for invoking a web service are to add the service reference, create the instance of the proxy object, add an event handler for its completion event, and invoke the web service asynchronously.
The Silverlight application contains four
TextBox controls that represent the To
address, From address, Subject, and Body of the email message. The To
address can contain a series of email addresses delimited by a
You can manually load the default values into the
TextBox controls by setting each
Text property value. After the user has
entered the values, you can retrieve the values from the
TextBox controls to pass them to the web
service’s web method by manually pulling the values from the controls
and into local variables.
Although this technique works, another option is to take
advantage of the XAML-based binding techniques. A
MessageInfo class exists in the example code
for the purpose of storing the values from these fields and acting as
a mediator for the
controls. Example 5-3 shows the code for the
MessageInfo class. An instance of
MessageInfo class is created and the
default values are initialized in the constructor of the
EmailClient Silverlight 2 control. Example 5-4 shows a snippet of
the control’s XAML and its bindings.
Example 5-3. MessageInfo class
C# public class ...