Sort multidimensional array in PHP.

sortMultidimensionalArray.php

<?php

function sortMultidimensionalArray($arr, $attr){

// Comparison function 
$compareTIME = function ($el1, $el2) use ($attr){
    $datetime1 = strtotime($el1[$attr]); 
    $datetime2 = strtotime($el2[$attr]); 
    return $datetime1 - $datetime2; 
};

$compareSTR = function ($el1, $el2) use ($attr){
    $s1 = $el1[$attr]; 
    $s2 = $el2[$attr]; 
    $coll = collator_create( 'en_US' );
    return collator_compare( $coll, $s1, $s2 );
};
    
// Sort the array  
usort($arr, $compareSTR); 
return $arr;
}

$array = Array ( 
    Array ( 
        "name" => "Olivia Musterman", 
        "datetime" => "2019-02-22 11:29:45", 
        ), 
    Array ( 
        "name" => "Anna Musterman", 
        "datetime" => "2019-02-13 11:29:45", 
    ), 
    Array ( 
        "name" => "Xenia Musterman", 
        "datetime" => "2019-02-15 11:29:45", 
    ) 
); 


// Print the array 
echo "<pre>";
print_r(sortMultidimensionalArray($array,'name'));
echo "<pre>";

?>