silverlight (3 Beta及4Beta介绍)

silverlight 3 Beta:
http://silverlight.net/GetStarted/silverlight3/default.aspx
Silverlight 3 Beta was unveiled at MIX09. It is a preview release which continues Silverlight’s track record of rapid innovation - introducing more than 50 new features, including support for running Silverlight applications out of the browser, dramatic video performance and quality improvements, and features that radically improve developer productivity. Combined with the continued innovation in Visual Studio and Expression Blend, Silverlight 3 empowers .NET developers to create cutting-edge Rich Internet Applications and media experiences.

2009-09-18:Silverlight 3新特性:http://silverlight.net/getstarted/silverlight3/
What's New in Silverlight 3
Fully supported by Visual Studio and Expression Blend, highlights of new features and functionality of Silverlight 3 include: major media enhancements, out of browser support allowing Web applications to work on the desktop; significant graphics improvements including 3D graphics support, GPU acceleration and H.264 video support; and many features to improve RIA development productivity. Also, in order to fully integrate all the .NET developer tools, Visual Studio 2010 will support a fully editable and interactive designer for Silverlight. New features in Silverlight 3 include:

Support for Higher Quality Video & Audio
With support for native H.264/Advanced Audio Coding (AAC) Audio, live and on-demand IIS7 Smooth Streaming, full HD (720p+) playback, and an extensible decoder pipeline, Silverlight 3 brings rich, full-screen, stutter-free media experiences to the desktop. New and enhanced media features in Silverlight 3 include:

Live and on-demand true HD (720p+) Smooth Streaming. IIS Media Services (formerly IIS Media Pack), an integrated HTTP media delivery platform, features Smooth Streaming which dynamically detects and seamlessly switches, in real time, the video quality of a media file delivered to Silverlight based on local bandwidth and CPU conditions.
More format choice. In addition to native support for VC-1/WMA, Silverlight 3 now offers users native support for MPEG-4-based H.264/AAC Audio, enabling content distributors to deliver high-quality content to a wide variety of computers and devices.
True HD playback in full-screen. Leveraging graphics processor unit (GPU) hardware acceleration, Silverlight experiences can now be delivered in true full-screen HD (720p+).
Extensible media format support. With the new Raw AV pipeline, Silverlight can easily support a wide variety of third-party codecs. Audio and video can be decoded outside the runtime and rendered in Silverlight, extending format support beyond the native codecs.
Industry leading content protection. Silverlight DRM, Powered by PlayReady Content Protection enables protected in-browser experiences using AES encryption or Windows Media DRM.
Empowering Richer Experiences
Silverlight 3 contains new 3D graphics, animation features, hardware accelerated effects and text improvements that enable designers and developers to create next generation Web visuals. Additional features include:

Perspective 3D Graphics. Silverlight 3 allows developers and designers to apply content to a 3D plane. Users can rotate or scale live content in space without writing any additional code. Other effects include creating a queue in 3D and transitions. (Learn More)
Pixel Shader effects. These software based effects include blur and drop shadow. In addition, you can also write your own effect. Effects can be applied to any graphical content. An example would be to make a button appear depressed on rollover you could use a drop shadow effect on the pressed visual state.
Bitmap Caching. Silverlight 3 dramatically improves the rendering performance of applications by allowing users to cache vector content, text and controls into bitmaps. This feature is useful for background content and for content which needs to scale without making changes to its internal appearance.
New Bitmap API. With Silverlight 3, developers can now write pixels to a bitmap. Thus, they can build a photo editor to do red eye correction, perform edits on scanned documents or create specials effects for cached bitmaps from elements on the screen.
Themed application support. Developers can now theme applications by applying styles to their Silverlight 3 applications and changing them at runtime. Additionally, developers can cascade styles by basing them on each other. (Learn More)
Animation Effects. Silverlight 3 provides new effects such as spring and bounce. These make animation more natural. Developers can also now develop their own mathematical functions to describe an animation.
Enhanced control skinning. Silverlight 3 provides easier skinning capabilities by keeping a common set of controls external from an application. This allows the sharing of styles and control skins between different applications.
Improved text rendering & font support. Silverlight 3 allows far more efficient rendering and rapid animation of text. Applications also load faster by enabling the use of local fonts.
Improving Rich Internet Application Productivity
New features include:

60+ controls with source code : Silverlight 3 is packed with over 60 high-quality, fully skinnable and customizable out-of-the-box controls such as charting and media, new layout containers such as dock and viewbox, and controls such as autocomplete, treeview and datagrid. The controls come with nine professional designed themes and the source code can be modified/recompiled or utilized as-is. Other additions include multiple selection in listbox controls, file save dialog making it easier to write files, and support for multiple page applications with navigation. (Learn More)
Managed Resources - Resource Libraries Support for merging libraries across files enhances the ability to create reusable resources and maintain large applications. (Learn More)
Deep Linking. Silverlight 3 includes support for deep linking, which enables bookmarking a page within a RIA.
Multi-page Application Visual Studio provides a framework for multi-page Silverlight Applications greatly simplifying inter-page communication and the creation of a uniform User Experience across pages. (Learn More)
Search Engine Optimization (SEO). Silverlight 3 enables users to solve the SEO-related challenges posed by RIAs. By utilizing business objects on the server, together with ASP.NET controls and site maps, users can automatically mirror database-driven RIA content into HTML that is easily indexed by the leading search engines.
Enhanced Data Support
Element to Element binding : UI designers use binding between two UI properties to create compelling UI experiences. Silverlight now enables property binding to CLR objects and other UI components via XAML, for instance binding a slider value to the volume control of a media player. (Learn More)
Data Forms. The Data Form control provides support for layout of fields, validation, updating and paging through data.
New features for data validation which automatically catch incorrect input based on rules in the bound data object. ()
Support for business objects on both client and server with n-Tier data support. Easily load, sort, filter and page data with added support for working with data. Includes a new built-in CollectionView to perform a set of complex operations against server side data. A new set of .NET RIA services supports these features on the server.
Improved performance
Application library caching, which reduces the size of applications by caching framework on the client in order to improve rendering performance.
Enhanced Deep Zoom, allows users to fluidly navigate through larger image collections by zooming.
Binary XML allows communication with the server to be compressed, greatly increasing the speed at which data can be exchanged.
Local Connection This feature allows communication between two Silverlight applications on the client-side without incurring a server roundtrip: for instance a chart in one control can communicate with a datagrid in another.
Advanced Accessibility Features
Silverlight 3 is the first browser plug-in to provide access to all system colors, allowing partially-sighted people to make changes such as high contrast color schemes for ease of readability by using familiar operating system controls.

Out of Browser Capabilities
The new out of browser experience in Silverlight 3 enables users to place their favorite Silverlight applications directly onto their PC and Mac, with links on the desktop and start menu—all without the need to download an additional runtime or browser plug-in. Further, the new experience enables Silverlight applications to work whether the computer is connected to the Internet or not—a radical improvement to the traditional Web experience. Features include:

Life outside the browser. Silverlight applications can now be installed to and run from the desktop as lightweight web companions. Thus, users can take their favorite Web applications with them, regardless of whether they are connected to the Internet or not.
Desktop shortcuts and start menu support. Silverlight applications can be stored on any PC or Mac computer’s desktop with links in the start menu and applications folder, and so are available with one-click access.
Safe and secure. Leveraging the security features of the .NET Framework, Silverlight applications run inside a secure sandbox with persistent isolated storage. These applications have most of the same security restrictions as traditional web apps and so can be trusted without security warnings or prompts, minimizing user interruptions.
Smooth installation. Because Silverlight applications are stored in a local cache and do not require extra privileges to run, the installation process is quick and efficient.
Auto-update. Upon launch, Silverlight applications can check for new versions on the server, and automatically update if one is found.
Internet connectivity detection. Silverlight applications can now detect whether they have Internet connectivity and can react intelligently including caching a users’ data until their connection is restored.
New Features in Expression Blend 3
The designer-developer workflow took another major step forward today with major innovations in Expression Blend 3 including: SketchFlow, a rapid prototyping capability that makes it easy to communicate design intent to stakeholders; design time sample data that enables the design and testing of applications without access to live data; direct import of Adobe Photoshop and Illustrator files; behaviors, extensible and reusable components that add interactivity to applications without writing code; a full code editor supporting C#, VB and XAML; and many more features that support an improved design and development experience. Features include:

SketchFlow. SketchFlow introduces a new set of features designed to make it easier for you to experiment with dynamic user experiences and create compelling prototypes. SketchFlow also helps communicate design ideas to other stakeholders, and makes it easier to collect in-context annotated feedback. SketchFlow enables the navigation and composition of an application to be modeled in a very visual manner from a simple prototype that uses a series of sketches, to something much more evolved. A prototype can be made as real and interactive as it needs to be to communicate design intent and SketchFlow leverages all Expression Blend's existing features.
Adobe Photoshop and Illustrator import. The powerful importers for both Adobe Photoshop and Adobe Illustrator enable smooth integration with workflows the designer already has in place. The designer has freedom to view and import Photoshop files layer by layer. Layers can be easily regrouped and elements retain their original formats; layers, layer positions, editable text and vectors remain available for editing within Expression Blend.
Behaviors. Add interactivity to your application, without having to write code. Behaviors can encapsulate complex design interactions into reusable components which can be directly applied to a user interface element in the application. Developers have access to a rich API that they can use to write their own triggers, actions, and behaviors for use in their Silverlight and WPF projects.
Sample data. Design time sample data makes it easy to build data-connected applications without access to live data. You can generate sample data or import sample data from an XML file and is available to controls on the artboard at design-time. You can extensively customize your sample data details, and you can easily switch between using sample data and using live data at run-time.
Improved design and development experience. Expression Blend 3 includes many features that improve the overall design experience including a brand new design surface making Blend more accessible to visual designers. Team Foundation Server support allows easier integration of the Blend user into Team System. Improved animation and easing functions, 3D transforms, visual effects and an improved visual state manager enable a great tooling experience. (Learn More)

微软7月10日发布了Silverlight 3的正式版本，即所谓的RTW版.中文部分摘自朱永光的文章:Silverlight 3新特性:支持高质量视频和音频
直播和点播的真高清（True HD 720P+）平滑流媒体
支持更多格式
全屏真高清回放
扩展的媒体格式支持
业界领先的内容保护技术

赋予更丰富的体验
透视3D图形
像素着色支持
位图缓存
新的位图API
主题化的应用程序支持
动画效果
增强的控件换肤功能
文本呈现和字体支持的改进

提高了RIA的生产力
有60多个控件，并附有源代码
支持深层链接（Deep Linking）
搜索引擎优化（SEO）
增强了数据支持
Elements到Element的绑定
数据窗体
为数据验证提供了新特性
支持业务对象

提升了性能
应用程序函数库缓存
增强了Deep Zoom功能。新版本的Deep Zoom Composor工具也同时发布。
支持二进制XML传输
支持本地连接

更高级的辅助功能（Accessibility）特性

脱离浏览器运行。对于这个特性的应用，大家可以访问这两个示例来体验：TED Player 和Webby Awards Player。
运行在浏览器之外
支持桌面快捷方式和开始菜单
更可靠和安全
流畅的安装过程
自动升级
互联网连接检测

与此同时，Silverlight 3 Tools for Visual Studio 2008 SP1也发布了最终版，具体的特性是：

提供了Visual Basic和Visual C#的项目模板
提供了XAML的智能感知和代码生成功能
可以调试Silverlight应用程序
可以远程调试Mac系统上的Silverlight应用程序
支持Web引用
提供了WCF模板
支持Team Build和命令行构建
支持可缓存透明平台扩展（cached transparent platform extensions）
支持Silverlight 3脱离浏览器应用程序的开发和配置

由于上述工具并没有提供Silverlig应用程序界面设计器，所以微软还推出了Expression Blend 3的RC版本。值得一提的是，这个版本附带了大家期待已久的SketchFlow原型设计工具。而Blend 3的新特性在MIX09的时候已经为大家所熟知了：
SketchFlow。微软给出了SketchFlow的一个概述，Christian Schormann在其博客上也介绍了SketchFlow的概念和SketchFlow Map的使用，他打算写一个系列的文章来介绍SketchFlow，大家可以可时常关注下。
支持Adobe Photoshop和Illustrator文件的导入。
行为。零代码为应用程序添加交互功能。
示例数据。方便地为应用程序生成示例数据，方便测试功能的运行和显示效果。
对设计和开发体验进行改进。

Silverlight作为微软重要的RIA开发平台的一部分，只是解决了前端界面的问题。所以微软炮制出了RIA Services这个框架，来辅助大家快速开发运行在中间层上的业务逻辑，以及控制对数据的访问。伴随着Silverlight 3的正式发布，RIA Services也更新到了7月预览版

Silverlight 3正式版发布后，国内的很多技术人员已经进行了尝鲜，如SilverLight3正式版(含Eclipse4SL)安装手记等.
最后，大家还可以经常访问Silverlight的开发团队博客 来获取最及时的消息。
微软将会在未来一个月内发布IIS Media Services 3.0（互联网信息服务）平滑流传输协议和一个受保护的可互操作的文件格式规范。IIS Media Services 3.0技术将会使得基于HTTP的内容流畅传送。
微软没有说新版本的Silverlight 4什么时候推出。
09-11-19
Silverlight 4beta可以下载并且有一些新的功能,可以参考:http://www.microsoft.com/silverlight/