This book is about Atlas, the code name for a collection of new Microsoft technologies that enable web developers, particularly ASP.NET 2.0 developers, to create web sites with pages that use Ajax more easily. Ajax-style pages provide a richer interface to users, they are more responsive, because the page can react immediately to users, and they can interact more or less immediately with the server. Atlas also includes tools for creating mashups: web applications that combine content from multiple sites, typically using the APIs provided by third-party web services. We’ll be exploring all of these capabilities and more throughout the book; this chapter tells you how to get started with Atlas, paints a broad picture of the technologies involved, and explains how Atlas works from an architectural point of view.
XMLHttpRequest object, which handles the requests from the client to the server. (Additional knowledge of XML
is a plus, but is not mandatory; we don’t use them much in this book.)
- Browser compatibility layer
Allows Atlas scripts to run in most browsers and eliminates the need to handcraft scripts for each browser you want to target. (Some browser-specific script is unavoidable, however, as you’ll see in Chapter 3.)
- Core services
- Base class library
Provides a number of .NET-like components, such as string builders and timers. You’ll learn about the Atlas
StringBuilderclass in Chapter 8.
- Script controls and components
Provides Atlas versions of standard HTML controls that are extended with capabilities like data binding, prepackaged behaviors (for example, drag-and-drop functionality), and tight integration with the Atlas 3lient libraries. You can program these controls and components directly, or you can use a new declarative markup called xml-script, which you’ll learn about in Chapters 5 and 6. If you are familiar with ASP.NET markup syntax, then you already understand (in general terms) the relationship of HTML controls, abstract programmable versions of these controls, and a declarative syntax.