note 90245 deleted from language.types.array by danbrown

Note Submitter: strata_ranger at hotmail dot com ---- Responding to genix at arctoz dot de, bear in mind that isset() returns FALSE if an array element has been explicitly assigned NULL. In most cases this is not a problem, however if you do at some point need to make a distinction between NULL and unset array elements you should use array_key_exists() instead of isset(). <?php $array = Array('foo' => null); // Outputs 'Foo does not exist' because $array['foo'] is NULL if (isset($array['foo'])) echo 'Foo exists'; else 'Foo does not exist'; // Outputs 'Foo exists' ...because it does if (array_key_exists($array, 'foo')) echo 'Foo exists'; else 'Foo does not exist'; ?>