Opening and closing code islands

There are two main ways to open a PHP code island (to enter PHP parsing mode), and you are welcome to choose which you prefer. The most common (and recommended) manner is to use <?php to enter PHP mode, and ?> to leave PHP mode, however you can also use the short tags version, <? and ?>.

The short version has one big advantage and one big disadvantage. The advantage is that you can output information from your script by using a special short tags hack, <?=. Here is how that looks:

<?="Hello, world!"

Here is the equivalent written using the standard open and closing tags:

    print "Hello, world!";

As you can see, the short tags version is much shorter, if a little harder to read. However, the big downside to the short version is that it clashes with XML, which also uses <? to open code blocks. This means that if you try to use XML and short-tagged PHP together, you'll almost certainly encounter problems - this is the primary reason people recommend using the normal open and close tags.

You can switch into and out of PHP mode by using <?php and ?> whenever you want to and as often as you want to.


Want to learn PHP 7?

Hacking with PHP has been fully updated for PHP 7, and is now available as a downloadable PDF. Get over 1200 pages of hands-on PHP learning today!

If this was helpful, please take a moment to tell others about Hacking with PHP by tweeting about it!

Next chapter: Comments >>

Previous chapter: Code blocks

Jump to:


Home: Table of Contents

Copyright ©2015 Paul Hudson. Follow me: @twostraws.