Various examples

This chapter presents some examples of how you can use the APIs of Core libraries. They are not meant to be exhaustive, ultimately the source code is the best documentation. These examples are here to get you started.

The Core itself along with its many system extensions provide another whole lot of examples.

Debugging

Before diving into the topic here are a few hints about debugging in TYPO3 CMS.

The TYPO3 Core provides a simple debug() (defined in EXT:core/Classes/Core/GlobalDebugFunctions.php). It wraps around \TYPO3\CMS\Core\Utility\DebugUtility::debug() and will output debug information only if it matches a set of IP addresses (defined in $GLOBALS['TYPO3_CONF_VARS']['SYS']['devIPmask']).

For example, the following code:

debug($_COOKIE, 'cookie');

will produce such an output:

Debug output

Typical TYPO3 debug output

Tip

The debug() function allows for adding your own debugging object. Put an instance of your class in $GLOBALS['error'] and its debug() method, receiving the same parameters as the original debug() function.

In general, look at class \TYPO3\CMS\Core\Utility\DebugUtility for useful debugging tools.