How to sort an array with PHP, ignoring the articles (a, an, the) in the beginning?

Question

Suppose I have the following array $books (the actual array is much larger):

Array
(
    [0] => The Mystic Masseur
    [1] => The Suffrage of Elvira
    [2] => Miguel Street
    [3] => A House for Mr Biswas
    [4] => Mr Stone and the Knights Companion
    [5] => The Mimic Men
    [6] => A Flag on the Island
    [7] => In a Free State
    [8] => Guerrillas
    [9] => A Bend in the River
    [10] => The Enigma of Arrival
    [11] => A Way in the World
    [12] => Half a Life
    [13] => Magic Seeds
)

When I use the sort function, the result is this:

Array
(
    [0] => A Bend in the River
    [1] => A Flag on the Island
    [2] => A House for Mr Biswas
    [3] => A Way in the World
    [4] => Guerrillas
    [5] => Half a Life
    [6] => In a Free State
    [7] => Magic Seeds
    [8] => Miguel Street
    [9] => Mr Stone and the Knights Companion
    [10] => The Enigma of Arrival
    [11] => The Mimic Men
    [12] => The Mystic Masseur
    [13] => The Suffrage of Elvira
)

But I would like to ignore the articles (a, an, the) in the beginning and would like to have a result like this:

Array
(
    [0] => A Bend in the River
    [1] => The Enigma of Arrival
    [2] => A Flag on the Island
    [3] => Guerrillas
    [4] => Half a Life
    [5] => A House for Mr Biswas
    [6] => In a Free State
    [7] => Magic Seeds
    [8] => Miguel Street
    [9] => The Mimic Men
    [10] => Mr Stone and the Knights Companion
    [11] => The Mystic Masseur
    [12] => The Suffrage of Elvira
    [13] => A Way in the World
)

I’ve tried:

$_books = array();
foreach($books as $book){
    if(substr($book, 0, 4) == "The "){
    $_books[substr($book, 4)] = $book;
    }
    else if(substr($book, 0, 3) == "An "){
    $_books[substr($book, 3)] = $book;
    }
    else if(substr($book, 0, 2) == "A "){
    $_books[substr($book, 2)] = $book;
    }
    else{
    $_books[$book] = $book;
    }
}
ksort($_books);
$books = array_values($_books);

But I know this is not the best solution because it has the risk of losing values (e.g. if there are both “A Fantasy” and “The Fantasy” in the input, there will be only “The Fantasy” in the output). So, what is the best solution?

Answer 1

Use a custom sort function:

function handleArticles($str) {
    list($first,$rest) = explode(" ",$str." ",2);
       // the extra space is to prevent "undefined offset" notices
       // on single-word titles
    $validarticles = array("a","an","the");
    if( in_array(strtolower($first),$validarticles)) return $rest.", ".$first;
    return $str;
}
usort($books,function($a,$b) {
    return strnatcasecmp(handleArticles($a),handleArticles($b));
});

Answer 2

Edited. Use custom function like this:

function customSort($a, $b) {
    $list = array(
        'The' => '',
        'A' => '',
    );
    $pattens = array();
    $replacement = array();
    foreach ($list as $from => $to){
        $from = '/\b' . $from . '\b/';
        $pattens[] = $from;
        $replacement[] = $to;
    }
     $a = preg_replace($pattens, $replacement, $a);
     $b = preg_replace($pattens, $replacement, $b);

     return strcmp($a,$b);
}
       $array = array("The Vendor", "The World of War", "A World of War");
       usort($array, 'customSort');

    print_r($array);

Result:

Array ( [0] => The Vendor [1] => A World of War [2] => The World of War )