Pro's and Con's to Upgrading PHP

[pipersdragon]

OK so, I currently use php 4, and since I'm only an intermidiate php coder, could someone explain to me why I should upgrade to php 5? I have seen some arcticles saying that php 5 complicates things, and causes some php 4 scripts to malfunction, but I havce also heard php4 ccan pose a threat to vulnerability. Can somebody help me out?

[scrowler]

after having written my reply twice, to have my browser crash before i can submit it, here goes again:

php5 has some added features and various reprogrammed (backend) functionality that probably won't come in useful at all unless you are an advanced programmer.

Originally Posted by php.net

PHP 5 and the integrated Zend Engine 2 have greatly improved PHP's performance and capabilities, but great care has been taken to break as little existing code as possible. So migrating your code from PHP 4 to 5 should be very easy. Most existing PHP 4 code should be ready to run without changes, but you should still know about the few differences and take care to test your code before switching versions in production environments.

there should be no reason to upgrade from php4 to php5 unless you want to explore these features, as php5 does complicate things for the reasons you discussed.

please refer to these pages:
migrating from php4 to php5
classes in php5