When I was first learning about web programming, it was difficult to grasp how javascript can interact with PHP. How do I manipulate data in the database with a client-side language? The answer, of course, is ajax, and if you’ve never used ajax, now is the time to learn how.
What is ajax?
Ajax is not a singular technology, it is a collection of technologies used for asynchronous communication between the client and server i.e. javascript grabbing data from a PHP script and displaying it on the page without refreshing the page. This is done through a DOM api called XMLHttpRequest, and I would encourage you to read a more in-depth view on its Wikipedia page. While this has some SEO implications, it also gives the programmer or designer a way to build rich, dynamic internet applications that don’t require a propriety plugin like Flash or Silverlight. Now that you have a basic understanding of ajax, lets try it out.
In this tutorial and demonstration, I will take a number from the user with an input box, and grab the row with that ID from the database and display it. This is not a useful example, but it does demonstrate the principles of moving data back and forth between the client and the server, and how we can display the data.