Complete Info of silverlight

An Overview of Silverlight

Silverlight enables development of the next generation of Microsoft .NET-based media experiences and rich interactive applications (RIAs) for the Web. Silverlight is delivered as a cross-platform and cross-browser plug-in that exposes a programming framework and features that are a subset of the .NET Framework and Windows Presentation Foundation (WPF).

Support

The industry has been abuzz about Silverlight since the beginning of 2007 when Microsoft began demonstrating its power at developer conferences. In fact, no other development technology has been so highly anticipated since the arrival of the .NET Framework and Silverlight resources and examples abound on the Web. To spark developer interest in Silverlight, Microsoft launched several community Web sites dedicated to Silverlight development including the Silverlight home page (http://www.microsoft.com/silverlight) and the Silverlight.net community Web site (http://silverlight.net/).

Early Adopters

In response to the overwhelming developer community anticipation for the arrival of Silverlight, many developers and companies have become early adopters of the technology.
Some example sites are listed below:

• World Series of Poker
• Discovery Channel
• The Emmys
• Home Shopping Network (HSN)
• World Wrestling Entertainment (WWE)
• Fox
• XBOX 360
• Netflix - uses Silverlight to allow subscribers to instantly watch movies on their PCs or Intel-based Macs.

Many of the published early adopter applications are featured in the Silverlight.net showcase.

The .NET Framework

Microsoft introduced the .NET Framework in 2000 as a new approach to software development. The .NET Framework borrowed ideas from the best practices in the software industry as well as brought new ideas to the table in an effort to meet developer needs and requests.
Virtually all programming languages manage data at some point. The primary reason that communication between applications created using C++, Visual Basic, Visual FoxPro, and other languages was difficult was because each language stored data being managed in a unique set of data types. For example, an integer in one language may not represent an integer in another language. Data needed to be converted to common data types to communicate between languages.
The .NET Framework introduced a common set of data types (the Common Type System) that is used by all .NET-compliant languages (C++, Visual Basic, C#, etc). Thus all languages can easily intercommunicate. Furthermore, all .NET-compliant languages render a common result when compiling code, Microsoft Intermediate Language (MSIL). (see footnote) MSIL can be deployed to any platform running the Common Language Runtime (CLR). Currently, the CLR is only available for Microsoft Windows although an open source version of the CLR was created for Linux (called the Mono Project). Code written by using the .NET Framework is compiled instead of interpreted resulting in much better performance than Java and competing technologies.
Microsoft took the Web development industry by storm with their .NET upgrade to ASP. ASP.NET put a new face on Web development through a compiled code architecture and improved state management and it provides access to the full functionality of the .NET Framework. ASP.NET is built around XML, supports the latest Web development standards, and allows for the creation of advanced Web Services.
The .NET Framework also provides improved data access and database integration through ADO.NET. For more information, see MSDN.
There are many more features and benefits of the .NET Framework than those mentioned here. The .NET Framework has become the leading software development environment available.

Introducing Silverlight

What's New in the .NET Framework

As of the writing of this course, version 3.5 of the .NET Framework has been released. Version 3.5 includes features that encompass all facets of Windows, Web, and network development:

• Includes just under 10,000 classes, methods, and properties.
• Complies with the latest Web development standards.
• Introduces revolutionary technologies used in Windows Vista development, rich media and user experiences, workflow management, security and authorization, and complete distributed communication protocols.

The .NET Framework can also be fully extended by developers to create custom classes and types. The functionality of the .NET Framework spans the server, the workstation, and the Web. The four primary additions to the .NET Framework as of version 3.0 are:

1. Windows Presentation Foundation (WPF)
2. Windows Communication Foundation (WCF)
3. Windows Workflow Foundation (WF)
4. CardSpace

Windows Presentation Foundation (WPF)

WPF is used to develop elaborate user interfaces like those that adorn Windows Vista and managed advanced media streaming and integration. WPF is the a complete revamp of Windows Forms so that user interface, graphic, and media development is now designed around the .NET Framework.

Windows Communication Foundation (WCF)

WCF encompasses the ASP.NET Web Services and .NET remoting functionality that was contained in the .NET Framework 2.0 as well as new communication technologies.

Windows Workflow Foundation (WF)

WF is used to model complex workflow processes.

CardSpace

CardSpace is the embodiment of new security and user authorization functionality.

ASP.NET AJAX

ASP.NET AJAX was developed to improve performance in the browser by making post backs and calls between the browser and server asynchronously. ASP.NET AJAX uses new built-in types and controls and JavaScript.
Both ASP.NET and ASP.NET AJAX are heavily dependent upon the ASP.NET page event life cycle, are tightly coupled to the server, and have a tough time competing with advanced, media-rich plug-in solutions such as Adobe Flash. Additionally, it is difficult to create Web applications that offer a consistent experience across all supported browsers and platforms by using ASP.NET and AJAX. In 2006, Microsoft began developing a solution to extend into the browser and offer media experiences more robust than competing plug-in solutions.
In 2007, Microsoft introduced Silverlight. (see footnote) Silverlight is a free plug-in that encompasses a subset of functionality from the .NET Framework and WPF. In a manner similar to the JVM (see footnote), Silverlight runs in the browser as a "sandbox" - a secure zone installed into the browser that accommodates Silverlight functionality while completely protecting the host platform from any possibly adverse actions performed by Silverlight.

Silverlight Architecture

Unlike ASP.NET, the bulk of Silverlight processing occurs on the client machine thus decreasing server resource utilization and improving the Web experience on the client. The figure below shows the difference between ASP.NET processing and Silverlight processing:
When a client initially attempts to run a Silverlight application, if the Silverlight plug-in has not been installed on the client machine, it will be downloaded and installed. Upon subsequent requests to run the application, the application will instantiate on the client machine and make requests for resources from the server only when necessary. The Silverlight plug-in can be thought of as a scaled-down version of the full .NET Framework. It only contains those classes and functionality that are applicable to a Silverlight Web client and those were streamlined and optimized for use on the Web client machine.
Silverlight was designed using the same design paradigm as ASP.NET. Each page of a Silverlight application includes an associated code behind file that includes the code that handles events fired by the page. Silverlight resembles WPF in that it uses Extensible Application Markup Language (XAML) to construct the user interface (presentation layer). As Silverlight applications are composed of text-based files that include markup and code, they can be created using any text editor; however, more advanced tools and development environments such as Visual Studio or Expression Blend simplify the task significantly.

Silverlight Technologies

Version 1.0 of Silverlight used JavaScript and supported the industry-leading Windows Media Services enabling delivery of audio and video that includes 2D and vector graphics.
Version 2 includes all features of version 1.0 and:

• support for the .NET Framework.
• support for .NET-compliant programming languages such as C#, Visual Basic, Python, and Ruby.
• support for database operations and language-integrated query (LINQ).

The figure below illustrates the major differences between version 1.0 and version 2:
The diagram located at gives a broad picture of the technologies to be supported by Silverlight version 2.

Silverlight Hosting

Microsoft Silverlight functionality is completely encapsulated within the Silverlight plug-in. Web applications typically require the server hosting the Web application to meet minimum requirements. Silverlight applications simply require a Web server to be equipped as they would be for hosting HTML documents. Silverlight applications can be hosted on any Web server accessible to the target audience. The two most commonly used Web servers are Microsoft Internet Information Server (IIS) and Apache.
Executing a Silverlight application on a Web client machine is a two step process. First, the application will detect if the Silverlight plug-in is installed on the Web client machine. If the plug-in is not installed, the user will be prompted with an option to download the plug-in. If the user opts to do so, a request will be made of the Web server to download and install the plug-in. The Silverlight plug-in is embodied in a .dll executable file that is loaded into the Web client browser memory once installed. The only interaction required by the Web client when installing the Silverlight plug-in is to grant permission for the plug-in to be installed. Various Web servers, including Microsoft Internet Information Server (IIS), may require slight configuration modifications so that the Silverlight executable file will be downloaded to the Web client when requested.
Second, once the Silverlight plug-in is installed on the Web client machine, the Silverlight application itself must be downloaded. A Silverlight application may consist of many types of files. Slight configuration modifications may be necessary on the Web server, such as MIME types, so that XAML and XAP files are associated with Silverlight and downloaded correctly to the Web client machine when requested.
Once the Silverlight plug-in is installed on a Web client machine and a Silverlight application is downloaded, the Silverlight application is then hosted on the Web client machine. There are some requirements necessary for the Web client machine as discussed in the sections below, however all media players, audio and video codecs, compilers and the runtime are encapsulated in the Silverlight plug-in.

Supported Platforms

Silverlight can be installed on Windows and Macintosh machines. Silverlight applications run within the confines of a plug-in. There are many benefits to using a plug-in with the primary benefit being consistency across implementations. A plug-in application can provide a consistent result in every instance where it is supported. Other plug-in solutions, such as Adobe Flash, have become popular due to consistency across implementations. For instance, a plug-in application should deliver a consistent result regardless of whether it is displayed using Internet Explorer on Windows or Safari on a Macintosh.
Silverlight 2 is currently supported on the platforms discussed below.

Platforms that Support Silverlight 2

Operating System	Browser
Windows Vista Windows XP SP2 Windows 2000 Windows Server 2003	Internet Explorer 7+ Firefox 1.5+ Google Chrome
Macintosh OS 10.4.8+ (Intel Based)	Safari Firefox 1.5+

Linux

Many developers are unaware that a version of the .NET Framework exists for the Linux operating system. Linux is an open source operating system that is supported heavily in the online community. The version of the .NET Framework that supports Linux is named the Mono project and was also developed by the open source community. The developers of the Mono project keep the project close to in sync with the .NET Framework when updates are released by Microsoft and created an initial, limited version of Silverlight (called "Moonlight") that supports Linux in approximately 21 days!  You can get up to date information on this project at http://www.mono-project.com/Moonlight.

Future Platforms

The Silverlight plug-in renders graphics and multimedia using a vector-based graphics engine. Vector graphics can easily be scaled from very small displays to very large displays of varying resolutions with virtually no loss of image quality. Silverlight on a Windows Mobile device will accommodate delivering live, streaming, high quality video to smart phones and similar devices. The goal is to enable developers to deliver rich interactive applications (RIA) to any type of device.
Microsoft has announced support for Silverlight on mobile devices with a limited initial support for Windows Mobile and the Nokia S60 models. You can learn more about this future support at

silverlight

What is Silverlight?

Silverlight is a new cross-browser, cross-platform implementation of the .NET Framework for building and delivering the next generation of media experiences and Rich Interactive Applications(RIA) for the web. It runs in all popular browsers, including Microsoft Internet Explorer, Mozilla Firefox, Apple Safari, Opera. The plugin required to run Silverlight is very small in size hence gets installed very quickly.
It is combination of different technolgoies into a single development platform that allows you to select tools and the programming language you want to use. Silverlight integrates seamlessly with your existing Javascript and ASP.NET AJAX code to complement functionality which you have already created.
Silverlight aims to compete with Adobe Flash and the presentation components of Ajax. It also competes with Sun Microsystems' JavaFX, which was launched a few days after Silverlight.


Currently there are 2 major versions of Silverlight:
Silverlight 1.0 and Silverlight 2.0( previously referred to as version 1.1).

Silverlight 1.0 :

Silverlight 1.0 consists of the core presentation framework, which is responsible for UI, interactivity and user input, basic UI controls, graphics and animation, media playback, DRM support, and DOM integration.
Main features of Silverlight 1.0 :

1. Built-in codec support for playing VC-1 and WMV video, and MP3 and WMA audio within a browser.
2. Silverlight supports the ability to progressively download and play media content from any web-server.
3. Silverlight also optionally supports built-in media streaming.
4. Silverlight enables you to create rich UI and animations, and blend vector graphics with HTML to create compelling content experiences.
5. Silverlight makes it easy to build rich video player interactive experiences.

Silverlight 2.0 :

Silverlight 2.0 includes a version of the .NET Framework, with the full Common Language Runtime as .NET Framework 3.0; so it can execute any .NET language including VB.NET and C# code. Unlike the CLR included with .NET Framework, multiple instances of the CoreCLR included in Silverlight can be hosted in one process. With this, the XAML layout markup file (.xaml file) can be augmented by code-behind code, written in any .NET language, which contains the programming logic.
This version ships with more than 30 UI controls(including TextBox, CheckBox, Slider, ScrollViewer, and Calendar controls), for two-way databinding support, automated layout management (by means of StackPanel, Grid etc) as well as data-manipulation controls, such as DataGrid and ListBox. UI controls are skinnable using a template-based approach.
Main features of Silverlight 2.0 :

1. A built-in CLR engine that delivers a super high performance execution environment for the browser. Silverlight uses the same core CLR engine that we ship with the full .NET Framework.
2. Silverlight includes a rich framework library of built-in classes that you can use to develop browser-based applications.
3. Silverlight includes support for a WPF UI programming model. The Silverlight 1.1 Alpha enables you to program your UI with managed code/event handlers, and supports the ability to define and use encapsulated UI controls.
4. Silverlight provides a managed HTML DOM API that enables you to program the HTML of a browser using any .NET language.
5. Silverlight doesn't require ASP.NET to be used on the backend web-server (meaning you could use Silverlight with with PHP on Linux if you wanted to).
6. Silverlight 2 includes Deep Zoom, a technology derived from Microsoft Live Labs Seadragon. It allows users to zoom into, or out of, an image (or a collage of images), with smooth transitions, using the mouse wheel. The images can scale from 2 or 3 megapixels in resolution into the gigapixel range, but the user need not wait for it to be downloaded entirely; rather, Silverlight downloads only the parts in view, optimized for the zoom level being viewed.
7. Silverlight 2 also allows limited filesystem access to Silverlight applications. It can use the operating system's native file dialog box to browse to any file (to which the user has access).

 

How Silverlight would change the Web:

1. Highest Quality Video Experience : prepare to see some of the best quality videos you have seen in your life, all embedded in highly graphical websites. The same research and technology that was used for VC-1, the codec that powers BluRay and HD DVD, is used by Microsoft today with its streaming media technologies.
2. Cross-Platform, Cross-Browser : Finally build web applications that work on any browser, and on any operating system. At release, Silverlight will work with Mac as well as Windows!  The Mono project has also already promised support for Linux!.
3. Developers and Graphic Designers can play together! : Developers familiar with Visual Studio, Microsoft.net will be able to develop amazing Silverlight applications very quickly, and they will work on Mac's and Windows. Developers will finally be able to strictly focus on the back end of the application core, while leaving the visuals to the Graphic Design team using the power of XAML.
4. Cheaper : Silverlight is now the most inexpensive way to stream video files over the internet at the best quality possible. Licensing is dead simple, all you need is IIS in Windows Server, and you’re done.
5. Support for 3rd Party Languages : Using the power of the new Dynamic Language Runtime, developers will now be able to use Ruby, Python, and EcmaScript! This means a Ruby developer can develop Silverlight applications, and leverage the .net Framework!
6. Cross-Platform, Cross-Browser Remote Debugging : If you are in the need to debug an application running on a Mac, no problem! You can now set breakpoints, step into/over code, have immediate windows, and all that other good stuff that Visual Studio provides.
7. The best development environment on the planet : Visual Studio is an award winning development platform! As it continues to constantly evolve, so will Silverlight!
8. Silverlight offers copy protection : Have you noticed how easy it is to download YouTube videos to your computer, and save them for later viewing ? Silverlight will finally have the features enabling content providers complete control over their rich media content! Streaming television, new indie broadcast stations, all will now be possible!
9. Extreme Speed :There is a dramatic improvement in speed for AJAX-enabled websites that begin to use Silverlight, leveraging the Microsoft .net framework.

Getting Started With SilverLight :

In order to create Silverlight applications with following :

Runtime :

Microsoft Silverlight 2.0 : The runtime required to view Silverlight applications created with .NET Microsoft.

Developer Tools :

Microsoft Visual Studio 8.0 : The next generation development tool.
Microsoft Silverlight Tools for Visual Studio 2008 : The add-on to create Silverlight applications with Visual Studio 2008. This install will also install the Silverlight Developer Runtime and the Silverlight SDK. This add-on works with all versions of Visual Studio 2008 Service Pack 1, including Visual Web Developer.

Designer Tools :

Download the Expression designer tools to start designing Silverlight application.
Expression Blend 2.5The latest offering from Microsoft to create Silverlight content is Expression Blend 2.5 June 2008 Preview.

Software Development Kit:

Microsoft Silverlight Software Development Kit: Download this SDK to create Silverlight Web experiences that target Silverlight 2.0. The SDK contains documentation, tools, Silverlight ASP.NET controls and the libraries needed to build Silverlight applications.
Eclipse Tools for Silverlight :
An Open Source, feature-rich and professional RIA application development environment for Microsoft Silverlight in Eclipse.

Advantage/disadvantages of Javascript

This article discusses the good and the bad points of using JavaScript in your website designs. It points out the areas where JavaScript excels as a web based programming language and also describes situations where its use can actually detract from the performance of a website.
First of all, JavaScript is a browser based programming language that actually runs client side. This means that any code that you write in JavaScript is delivered along with your web pages and the scripts that you write actually run from within the users' browser rather than directly on the server that is serving the web page. There are situations where JavaScript is an excellent solution for implementing neat features in a web design but there are also situations where using JavaScript can hurt your websites performance. It is my aim in this article to describe the best ways to use JavaScript and how to circumnavigate the downsides of using this versatile and powerful scripting language.
JavaScript for Web Design - The Advantages
JavaScript is an excellent solution to implement when validating input forms on the client side. This means that if a user forgets to enter his name in a form for instance a JavaScript validation function can popup a message to let him know about the omission. This is a far better solution that having a server side validation routine handle the error because the server does not have to do any additional processing. An asp or php routine could be written to achieve the same task but the JavaScript would not allow the form to be submitted unless it was completed properly in the first place, a much more robust solution!
Another area where JavaScript excels is in the creation of dynamic effects such as rollover images and scripted slideshows, where its use has become commonplace. Because JavaScript runs inside the clients browser it can be used to change the appearance of the users screen after the page has been sent by the server. This allows it to create some very impressive dynamic image effects.
JavaScript for Web Design - The Disadvantages
One of the major draw backs to using JavaScript is that it tends to severely bloat web pages. JavaScript code can quickly add up to hundreds of lines of code if you are using it to do anything even remotely interesting. That said the problem of large chunks of JavaScript code is easily solved by storing the JavaScript code off into separate JavaScript source files that have a .js extension. This cleans up your web page code because the JavaScript code is stored separately to the HTML page itself, leaving a much cleaner and more readable web page.
Because of JavaScript's tendency to bloat web pages it can be very detrimental to the search engine friendliness of your web site. This is because when a search engine arrives at your site looking for quality content and keywords to determine what your page is al about, the last thing it wants to see is hundreds of lines of JavaScript code. Again, this problem is easily solves by neatly storing JavaScript code away in script files with a .js extension and linking to the script file in your HTML documents.
Conclusion:
JavaScript is a feature rich and useful browser based script that if used properly can achieve some great effects and improve the experience for the end user. There are drawbacks to its use in that it tends to bloat web pages. The key thing to remember is to get the best of both worlds by using JavaScript code in external script files. That way the code is separated from your content so you get all the benefit of JavaScript functionality but without the adverse effects of the associated code bloating.

PageLifecycle

Complete page life cycle scenario

In this walkthrough, we will go through each of the relevant page life cycle events and see what role Viewstate has in each of these events. In this examplem, we have as ASP.NET page with the following characteristics:

• It contains a single Label control (lbl) with its “Text” property set to “statictext”
• It contains a Button control (btnA) with code in its event handler that sets the “Text” property of “lbl” to “dynamictext”
• It contains a Button control (btnB) whose purpose is to cause a page postback

Now, let us examine what will happen during the page life cycle.

1. The page is first loaded
   1. The compiled class of the page is generated and “statictext” is assigned to “lbl.Text”
   2. Tracking for Viewstate is enabled in the “InitComplete” event
   3. “LoadViewState” is not fired because there is no postback
   4. “SaveViewstate” is fired, but nothing happens because no change of state is recorded
   5. The page is rendered with the value “statictext” inside “lbl”
2. btnA is clicked
   1. The previously generated compiled class is handed the request; “lbl.Text” is set to “statictext”
   2. Tracking for Viewstate is enabled
   3. “LoadViewState” is fired, but nothing happens because no change of state was recorded in the previous page visit
   4. “RaisePostbackEvent” event is executed and “btnA” click event handler is fired; “lbl.Text” is set to “dynamictext”; since tracking is enabled at this stage, this item is tracked (marked as “Dirty”).
   5. “SaveViewState” is fired; “dynamictext” is serialized and stored in the __VIEWSTATE field
   6. The page is rendered with the value “dynamictext” inside “lbl”
3. btnB is clicked
   1. The previously generated compiled class is handed the request; “lbl.Text” is set to “statictext”
   2. Tracking for Viewstate is enabled
   3. “LoadViewState” is fired; since a change of state was recorded from the previous page visit, __VIEWSTATE is loaded and the value “dynamictext” is extracted; this value is then assigned to “lbl”
   4. “RaisePostbackEvent” event is executed; nothing happens here because “btnB” has no event handler for its “Click” event
   5. “SaveViewState” is fired, but nothing happens because no change of state is recorded
   6. The page is rendered with the value “dynamictext” inside “lbl”