Services are reusable components that do not require a user interface. In Silverlight Composite Application service is any class. For public accessibility it can be registered in Application.Resources. In most cases modules are responsible for service registration.

To create a service

To create a service and register it in Application.Resources you can:

• Specify the required service in App.xaml of your application.
  <Application.Resources>
    <scabsvc:ScriptManager x:Key="ScabScriptManagerService" />
    <scabsvc:Trace x:Key="ScabTraceService"/>
  </Application.Resources>
  
• Or create and register it from code like this:
  ScabApplication app = ScabApplication.Current;
if (!app.Resources.Contains("ScabScriptManagerService"))
  app.Resources.Add("ScabScriptManagerService", new ScriptManager());

Getting references to services

To access services from code you should use the following code template:

Registering services to access from JavaScript code

Silverlight supports objects to be accessible from JavaScript. Services can use this possibility to publish their functionality.

1. Mark your service with [ScriptableType] attribute.
2. Mark your service members with [ScriptableMember] attribute.
3. Register your service object for scriptable access by JavaScript code using HtmlPage.RegisterScriptableObject method.

Example

Services.zip (70.67 kb)

The following example contains Service module assembly and CompositeApplication application. Service assembly contains Service service class and ServiceModule module class declaration. Service class declares one ShowMessage module. This method shows message box with the specified string parameter. Service class and its method are marked with scriptable attributes to allow access from JavaScript. ServiceModule registers Service instance both in Application.Resources and calling HtmlPage.RegisterScriptableObject static method.

CompositeApplication specifies ServiceModule to load at App.xaml file. After that Page.xaml.cs gets reference to service and calls ShowMessage method from managed code and emulating JavaScript call.