Ajax for Web Application Developers

Chapter 2. The Request Now that you have some background on Ajax and a brief overview of what we will set out to accomplish with the sample project, you are ready to assemble the request. This chapter will introduce the inner workings of the...

An In-Depth Look at XMLHttpRequest The XHR (XMLHttpRequest) object is the core of the Ajax engine. It is the object that enables a page to get data from (using the GET method) or post data to (using the POST method) the server as a background requ...

Creating the Object With a better understanding of the XHR and different request models, we can now focus on creating the object. Creating the request object is trivial in comparison to the power that is unleashed when applying it to a project. ...

Asynchronous Data Transfers If you are new to data transfers and you are not exactly sure what the term asynchronous data transfers actually means, don't worryyou are probably unaware of the fact that you already understand them and have used them...

The Ready State After the XHR object has been created and the request has been made, we need a way to know when the response has been received. This is where the onreadystatechange event handler is used. The onreadystatechange event handler fires ...

HTTP Status Codes and Headers The request status of the Ajax object is equivalent to the HTTP status of the file that is being requested. HTTP status codes represent the response from the server based on the status of the file that is being reques...