Dissecting Hello World!
This blog dissects the Silverlight 2 Hello World! application created in this previous blog: Silverlight Blog Post 2 - Hello World!
Below is a screen shot of the Visual Studio 2008 Solution Explorer for the Hello World! solution. Following it is an explanation of items 1-6, some of the more important parts of the solution.
The solution consists of two Visual Studio projects: 1) HelloWorld the Silverlight 2 application project and 2) HelloWorld.Web an ASP.NET web application that hosts the HelloWorld Silverlight 2 application.
1. HelloWorld
This is the Silverlight 2 application project that defines the Hello World! application.
2. App.xaml and App.xaml.vb
These files define the Hello World! Application class. Every Silverlight application has one application class. These files are used to define resources that will be made available to all the pages in your application and to define the way for your application should to react to application events such as startup, shutdown, and error conditions.
For more information visit: Silverlight Application Class and Silverlight Application Class Members
3. Page.xaml and Page.xaml.vb
These files define the application's Page class.
By default, Visual Studio creates one page class using a Silverlight UserControl and makes it the applications root visual (main application interface). You can add additional pages and navigation code to navigate from page to page by displaying them in the root visual.
For more information visit: Silverlight UserControl and Silverlight UserControl Members and RootVisual
4. HelloWorld.Web
This is the ASP.NET web application that hosts the Silverlight application. The site is used to test the Silverlight application. It can be modified and deployed to a web server. Alternatively you can add the application .xap file (.xap file explained next) to a larger web site and add a page on that site to serve up the application.
5. HelloWorld.xap
This file contains the Silverlight application created each time the solution is rebuilt. This is a zip file with a .xap file extension. When you build the solution Visual Studio bundles up all the generated parts and pieces of the Silverlight application into this file and pushes it into the ClientBin directory of the web application.
For more information visit: Structure of the Silverlight XAP File and Deploying Silverlight Applications
6. HelloWorldTestPage.aspx and HelloWorldTestPage.html
These pages demonstrate two ways to serve up the application (HelloWorld.xap file).
The .aspx page demonstrates how to serve up the control in an Asp.Net page. The .aspx file is an ASP.NET web form that uses Asp.Net's Silverlight web control to host the Silverlight application. It contains an Asp.Net Silverlight server control. Like other ASP.NET web server controls, the Silverlight control creates the test page markup dynamically, when it's processed on the server. By default this is the startup page of the web application Visual Studio created for the solution.
The .html page demonstrates how to serve up the application in an HTML page. The .html page is generated once, when the ASP.NET website is first created, not every time the project is built. By default this page is not displayed when you run the Visual Studio project. To try it make it the startup page of the web application.
Next Silverlight 2 blog post: Expanding the HelloWorld! Silverlight 2 Application