PHP array_change_key_case() Function

PHP array_change_key_case() Function

The array_change_key_case() function in PHP is used to change the case of all keys present in the specified array. It returns an array with all keys in the specified array to lowercase or uppercase.

Syntax

array_change_key_case ( array $array [, int $case ] )

Parameter

array(required)- This parameter represents the array to work upon.

case(optional)- This parameter signifies the cases i.e. CASE_UPPER or CASE_LOWER (default)

Return

This function returns an array with its keys lower or uppercased if the specified array parameter is an array else it returns FALSE.

Errors/Exception

This function throws an E_WARNING if the specified array parameter is not an array.

Example 1

'0', 'B'=>'1', 'C'=>'2', 'D'=>'3');
 //which change the upper-cased array to lower case 
 print_r(array_change_key_case($arr)); //by default it converts to lower case
 ?> 

Output

Array
 (
     [a] => 0
     [b] => 1
     [c] => 2
     [d] => 3
 ) 

Example 2

"22","Bikash"=>"32","Sukla"=>"43","Varun"=>"20");
 //passing the case as CASE_UPPER
 $case=CASE_UPPER;
 //which change the lowered case array to Upper case 
 print_r(array_change_key_case($arr, $case));
 ?> 

Output

Array
 (
     [REEMA] => 22
     [BIKASH] => 32
     [SUKLA] => 43
     [VARUN] => 20
 ) 

Example 3

Output

PHP Warning:  array_change_key_case() expects parameter 1 to be array, int given in /workspace/Main.php on line 5