The title is not about book's title. :) I just want to share how can i got understanding when learning ASP .NET AJAX.
I know, when first time i learn about ASP .NET AJAX, it lacks a lot of samples and documentations. You can googling to find out. But you can still confuse which one should i have to start first. So, maybe my experience can help you to understand better. This is what i've done to understand ASP .NET AJAX :
1) Learn how XMLHttpRequest object works first. As a good start, you can refer to this link: http://www.w3schools.com/xml/xml_http.asp or http://www.w3.org/TR/XMLHttpRequest/ if you want to understand everything about it. Just take a few minutes a day to read. This is a basic level that you should passed.
2) Because the glue is a scripting language (JavaScript is commonly used), like or dislike you have to learn JavaScript too. Even when dealing with ASP .NET AJAX. Know it well will provide a better result. Honestly, I also impressed that JavaScript can also support inheritance, interface, etc etc. Huehehehe, shame on me. :) This knowledge will help you to understand and define a best scenario in your case. Not to be master in JavaScript, but known common scenario is a must.
3) Since you are working on client area, knowledge about Document Object Model (DOM) is a must also. This is because you have to send and receive a data format that you are using with. It's maybe just a simple string, complex string, XML, or JSON data format. You have to construct it to whatever DOM object you are using (maybe a DIV, a SPAN, an UL, a LI, a TABLE, and the others) dynamically. So you have familiar with appending a child nodes object from it's DOM object you are working with.
4) Usually DOM is combined with Cascading Style Sheet (CSS). You do not have to master in CSS, but know common scenario should be helpful for you. A lot tutorials out there. Just use uncle Google to find it. :)
5) Choose an Ajax implementation. You can choose whatever you want, AjaxPro, ASP .NET AJAX, Anthem.NET, MagicAJAX, etc ... etc. The core behind that is remain the same. It's XMLHttpRequest object. So, point one is a must.
6) Documentation is your friends ! Suppose that you choose ASP .NET AJAX. Since ASP .NET AJAX has it own implementations, so you have to explore the ASP .NET AJAX documentation. Microsoft provides a set of ASP .NET AJAX APIs information from ASP .NET AJAX docs. Make it your best friend. :) You can play with server-style approach or client-style approach. How ScriptManager works. How getting instance of ScriptManager. For example, if you understand how ASP .NET Page Life Cycle works, then you can understand the similar things when dealing with PageRequestManager. It has beginRequest, endRequest, pageLoaded, pageUnloaded, and other handlers that you can work with. So the APIs should be learned over and over again. This is an API consumer level. :)
7) If you working with sending and receiving data, then you should familiar with XML and JSON. You can read about JSON information here : http://www.json.org
8) Last, known how request and response work using Web Development Helper or similar. As i state before, analyze every packet from a very simple page to a complex one using ASP .NET AJAX APIs.
9) Practices make you perfect. Create a sample project again and again.
10) Read and collect articles from other blogger. There are a lot of good articles out there. For example :
The following members of the ASP.NET team frequently post ASP.NET AJAX information on their blogs:
Or this huge reference : http://searchstorage.techtarget.com/generic/0,295582,sid8_gci1228253,00.html#basics
Do i missed something ?
UPDATED: I forgot to mention about a good book from Brett McLaughlin "Head Rush Ajax".