C# 4 and .NET 4

1110 ❘ ChaPTer 38 silverliGht
private void OnRegistration(object sender, RoutedEventArgs e)
{
CurrentAttendee.EventId = (comboEvents.SelectedItem as Event).Id;
var client = new WebClient();
client.DownloadStringCompleted += (sender1, e1) =>
{
if (e1.Error != null)
{
NavigationService.Navigate(
new Uri("/ErrorPage", UriKind.Relative));
}
bool result = bool.Parse(XElement.Parse(e1.Result).Value);
if (result)
NavigationService.Navigate(
new Uri("/Success", UriKind.Relative));
else
NavigationService.Navigate(
new Uri("/ErrorPage", UriKind.Relative));
}
}
}
};
Uri requestUri = new Uri(String.Format(
"../../EventRegistrationDataService.svc/AddAttendeename='{0}'" +
"&email='{1}'&company='{2}'&registrationCode='{3}'&eventid={4}",
CurrentAttendee.Name, CurrentAttendee.Email,
CurrentAttendee.Company, CurrentAttendee.RegistrationCode,
CurrentAttendee.EventId), UriKind.Relative);
client.DownloadStringAsync(requestUri);
code snippet EventRegistration/Home.xaml.cs
When you run the application, you can register for an event.
Since version 3 of Silverlight, the Silverlight application does not have to use the networking stack from
the browser. The networking stack from the browser is limited in the methods of the HTTP requests it can
perform and returns only limited information on the response status codes. However, now it’s possible to
use a different networking stack that can be selected with the WebRequestCreator class from the System
.Net.Browser namespace. The following code snippet changes the networking stack to ClientHttp.
BrowserHttp is the second option in WebRequestCreator. This change switches the networking stack to
use all the networking options you’ve seen.
bool result = WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp);
broWser inTegraTion
Integration with a web browser often is an important part of using Silverlight. Silverlight 1.0 could only be
programmed using JavaScript. Luckily, this changed with Silverlight 2.0, but there are still many scenarios
where you might want to control HTML and JavaScript code from within the Silverlight control or invoke
.NET methods from JavaScript. Both are possible with the help of the namespace System.Windows
.Browser.
To demonstrate this integration by using the existing web solution, the following example creates a new
Silverlight project named JavaScriptInterop. This control is used to demonstrate both calling out to the
HTML code from within the Silverlight control and to invoke .NET methods from JavaScript.
www.it-ebooks.info