Decompiling Silverlight 2 Apps – Enter the XAP

When you build a Silverlight 2 application, you compile your source files (inc. XAML and embedded resources) into assemblies (dlls). Those assemblies (plus any 3rd party ones plus MS assemblies that are not part of Silverlight) are then collected together along with a manifest into a packaged archive – or in other words, a ZIP file. Except, the extension is changed to be a .XAP (pronounced "ZAP").