Iterator
PHP Manual

Iterator::key

(PHP 5 >= 5.0.0, PHP 7)

Iterator::keyReturn the key of the current element

Description

abstract public scalar Iterator::key ( void )

Returns the key of the current element.

Parameters

This function has no parameters.

Return Values

Returns scalar on success, or NULL on failure.

Errors/Exceptions

Issues E_NOTICE on failure.


Iterator
PHP Manual