.. _array_change_key_case()-validates-its-case-argument:

array_change_key_case() Validates Its Case Argument
===================================================
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		array_change_key_case() Validates Its Case Argument: ``array_change_key_case()`` accepts a second argument, either ``CASE_LOWER`` or ``CASE_UPPER``.
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	:twitter:title: array_change_key_case() Validates Its Case Argument
	:twitter:description: array_change_key_case() Validates Its Case Argument: ``array_change_key_case()`` accepts a second argument, either ``CASE_LOWER`` or ``CASE_UPPER``
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	:og:title: array_change_key_case() Validates Its Case Argument
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	:og:description: ``array_change_key_case()`` accepts a second argument, either ``CASE_LOWER`` or ``CASE_UPPER``
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``array_change_key_case()`` accepts a second argument, either ``CASE_LOWER`` or ``CASE_UPPER``. Until PHP 8.6, any other value was silently treated as ``CASE_LOWER``. In PHP 8.6, an invalid value throws a ``ValueError``.

PHP code
________
.. code-block:: php

   <?php
   
   var_dump(array_change_key_case(['A' => 1], 99));
   
   ?>

Before
______
.. code-block:: output

   array(1) {
     [A]=>
     int(1)
   }
   

After
______
.. code-block:: output

   array_change_key_case(): Argument #2 ($case) must be either CASE_LOWER or CASE_UPPER


PHP version change
__________________
This behavior changed in 8.6


See Also
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* `array_change_key_case() <https://www.php.net/array_change_key_case>`_


Error Messages
______________

  + `array_change_key_case(): Argument #2 ($case) must be either CASE_LOWER or CASE_UPPER <https://php-errors.readthedocs.io/en/latest/messages/array_change_key_case%28%29%3A-argument-%232-%28%24case%29-must-be-either-case_lower-or-case_upper.html>`_