PHP array_change_key_case() function

It is an inbuilt function of PHP. The array_change_key_case() function returns an array with all arrays keys in lower case or upper case.

Syntax

Important Note: If the second parameter is avoided then by default the keys of array will get converted to lowercase.

Example 1

Output:

Array(  [A]=>a  [E]=>e  [I]=>i  [O]=>o  [U]=>u  )

Example 2

Output:

Array ( [rahul]=> 10000  [ajay]=> 15000  [sid]=> 20000 )

Example 3

If two or more array keys will be the same after running array_change_key_case( ) function, the latest array will override the other.

Output:

Array ([A]=> Agra  [B]=> Bengaluru  [C]=> Chennai )

Example 4

If we ignore the second parameter in the function array_change_key_case( ) then the keys will be converted to lowercase.

Output:

Array ([rahul]=> 10  [vikas]=> 20  [sid]=> 25 )