Object Tree

The primary tree structure in WPF is the object tree. If you create an application page in XAML, then the tree structure is created based on the nesting relationships of the elements in the markup. If you create an application in code, then the tree structure is created based on how you assign property values for properties that implement the content model for a given object. In Windows Presentation Foundation (WPF), there are really two ways that the object tree is processed and conceptualized: as the logical tree and as the visual tree.


The position of WPF within the .NET Framework.

XBAP: XAML Browser APplications

XBAP allows for WPF applications to be used inside a browser. The .NET framework is required to be installed on the client system. Hosted applications run in a partial trust sandbox environment. They are not given full access to the computer’s resources and not all of WPF functionality is available.

WPF supports the creation of applications that run directly in a web browser. (So will WPF/E, when it is released.) They are called XAML Browser Applications (XBAPs), and have a .xbap extension. The power of this WPF support is that the exact same programming model is used for a XAML Browser Application as for a standard Windows application. Therefore, creating an XBAP isn’t much different than creating a standard Windows application. The main differences are as follows:

  • Not all features in WPF or the .NET Framework are accessible (by default)
  • Navigation is integrated into the browser (for Internet Explorer 7 or later)
  • Deployment is handled differently

XAML = Extensible Application Markup Language.

Although, XAML is a concept that is itself larger than WPF only, it is primarily used for creating the UI for WPF applications. It is to WPF what ASP.Net designer file code is to ASP.Net.

In WPF, XAML is used as a user interface markup language to define UI elements, data binding, eventing, and other features. In WF, workflows can be defined using XAML.

XAML elements map directly to common language runtime object instances, while XAML attributes map to Common Language Runtime properties and events on those objects. XAML files can be created and edited with visual design tools such as Microsoft Expression Blend, Microsoft Visual Studio, and the hostable Windows Workflow Foundation visual designer.

Commanding is an input mechanism in Windows Presentation Foundation (WPF) which provides input handling at a more semantic level than device input. Examples of commands are the Copy, Cut, and Paste operations found on many applications.

Commanding is “source-agnostic”, so it does not matter what control originated the Copy, as long as Copy is defined for that object. The Copy is going to be different for different objects such as Image, Text, etc.

The default HTTP handler for all Web handlers that do not have a UI and that include the @ WebHandler directive

Source: http://msdn.microsoft.com/en-us/library/bb398986.aspx

A Session is a unique instance of the browser. A single user can have multiple instances of the browser running on his or her machine. If each instance visits your Web application, each instance has a unique session.A session starts when a user accesses a page on a Web site for the first time, at which time they are assigned a unique session ID. The server stores the user’s session ID in the Session.SessionID property.