(PHP 5 >= 5.0.0, PHP 7) Unset value for an offset

(PHP 5 >= 5.1.0, PHP 7) Gets the current key

(PHP 5 >= 5.1.0, PHP 7) Gets the inner iterator

(PHP 5 >= 5.2.0, PHP 7) Returns an iterator for the current entry.

(PHP 5 >= 5.1.0, PHP 7) Determines acceptability

(PHP 5 >= 5.1.0, PHP 7) Checks validity of the current element

(PHP 5 >= 5.0.0, PHP 7) Return current array key

(PHP 5 >= 5.3.0, PHP 7) Gets the number of attached iterator instances

(PHP 5 >= 5.1.0, PHP 7) Get the current value

(PHP 5 >= 5.1.0, PHP 7) Check whether the current element of the iterator is acceptable