Reloading Images Using JavaScript
There are some situations where you want to reload an image without refreshing the page containing it. This is especially handy with CAPTCHA images, where you might want to give the user the option to get a new code in case the first is too hard to read.
It sounds simple enough, but then there is browser caching that you need to work around. Fortunately, this problem is easy to solve just by altering the URL of the source, adding a unique string to the end (such as a timestamp) as a GET parameter. Here is a little JavaScript function that will accomplish this:
Toggle Display of Page Elements with JavaScript
This mini tutorial explains how to show/hide elements on a web page using JavaScript. There are many reasons why you would want to do this, and luckily it is very simple.
All it takes is changing the display CSS property. Setting display: block; (the default for div tags) makes it visible, and display: none; makes it hidden. The advantage to using display is that other items on the page will move to close the void left by the hidden object.
What is AJAX?
AJAX stands for Asynchronous JavaScript and XML. Many modern websites, big and small, implement this technology in many different ways, but what exactly is it? Here is an explanation in simple terms...
An AJAX application is a web page that functions more like a desktop application than a traditional web page in that it feels more responsive. It works by transferring small pieces of information in the background and updating just the affected area of the page without reloading the whole thing. This not only speeds up web applications and lowers bandwidth consumption, it also increases end-user enjoyability. As AJAX becomes more popular, the gap between the Internet and desktop applications will become increasingly smaller.
