A Developer looking to move Ajax, must have a basic understanding of
- (X)HTML for displaying the data
- CSS for styling the data
- XML for receiving and formatting data
Ajax is used to drive a host of website and applications, some of the core features it is best suited for include:
- Auto saving user information
- Forms validation
- Cascading lists
- Auto completion of search text-boxes
- Realtime data refresh
- Dynamic content
- Instant actions, like voting and polls
Ajax sends a request to the server with the “open()” and “send()” methodology. The open method uses three augments, the first is method type, second is the defined URL of the server-side script and the third one specifies that the request should be handled asynchronously. Ajax uses XML HTTP Request Objects for browser-server communication. The mechanism for sending data and retrieving data from the server with Ajax is the XML Http Request object.
Ajax applications are 3 tier client-server apps. Heavily event-driven, graphics intensive (visual effects, rich visual controls), data orientated and often complex, as pages hold more controls and data than page orientated applications.
Ajax Development, advantages
Before AJAX, interactivity on web pages was laborious, slow and clunky. A user interaction required an updated version of the page to be generated on the server, sent to the browser and rendered there. Even a small change resulted in a full new page. This was wasteful of server resources, and provided for a very poor user experience
Ajax development changed all of this, by sending data and then receiving just the result for the interaction that triggered by it in order to update the relevant parts of the page.
Here are some of the main advantages that Ajax brings:
- Speed; reduces server traffic and the asynchronous nature ensures browser waiting times are minimal
- Interaction; small data transfers create for a more responsive experience
- Form validation; instant validation, done properly
- Bandwidth; extremely efficient, as no requirement to reload whole pages
Ajax Development, areas to consider
As with all development languages, there are areas that may be seen as disadvantages, in terms of Ajax these include
- It may increase development and design time, and increase code complexity
- Ajax indexing for search is more challenging
- Additional security considerations and constraints that must be considered, on the server-side Ajax is similar to regular web applications, on the client side, however, the JS code is more visible
Ajax Development, how Google have embraced Ajax
Ajax is a very popular development language amongst brands, sites and applications that have adopted Ajax development as part of their development ecosystem. Google utilise Ajax in a number of ways, and specifically for 2 of their most accessed services:
- Google Maps, a web mapping service developed by Google. It offers satellite imagery, street maps, panoramic street views and route planning. Ajax is utilised within the UI.
- Gmail, a free email service provider by Google. As of 2016, it was the most widely used web-based email provider with over 1 billion active users.
- Google Suggest, is the name of Google’s auto complete function. Suggestions are generated on the most frequently searched terms.