Microsoft AJAX Library Essentials is a book intended for ASP.NET developers who want to dive into client side programming and take full advantage of the Microsoft AJAX Library.
The book opens up with a brief history of the internet, http, and html. This chapter serves as a refresher for web programming veterans, or valuable information for beginners. Also provided for beginners are instructions for setting up your programming environment so you will be able to follow and try out the example code.
Next you are taken on a whirlwind tour of HTML, CSS, JavaScript, and the DOM and see examples of handling AJAX requests using XMLHttpRequest. If you have ever done any AJAX on your own (without the use of a library or framework), you could easily skip this entire chapter, if you have not, it is a wonderful tutorial on what goes on behind the scenes, and you get to see the inner workings that the libraries and frameworks provide easier access to.
The book does a very nice job of explaining how OOP principles can be used in JavaScript. I consider myself only an intermediate level JavaScript programmer, and I was able to follow the books explanations of what Closures, Prototypes, and what “this” means in relation to context and scope. For me it was an eye opening look into the potential power of JavaScript, which I have not used for much more than rudimentary AJAX calls and client-side data validation.
The rest of the book serves as a reference complete with code examples of how the Microsoft AJAX Library acts as a framework to make everything it just taught you easier. It shows the namespaces and method names (that will be familiar to Microsoft developers) which you can use in your own javascript code.
All in all, it is a nice reference and guide to using the Microsoft AJAX Library.
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