PHP array stringify

Question

In a lyrics application I'm coding, I'm using an array to print an artists table. The artists array looks like this:

$artists = [
    [ "Avril Lavigne"               ],
    [ "3 Doors Down"                ],
    [ "Celine Dion"                 ],
    [ "Evanescence"                 ],
    [ "Shania Twain"                ],
    [ "Green Day"                   ],
    //...
];

Before printing it, I do some modification to the array. I have a folder for each artist that contains the lyrics files. I add the folder names to the $artists array for later use:

$folder_fix = [
    [" ",   "_" ],
    [".",   ""  ],
    ["&",   "n" ],
];

for ($i = 0; $i < count($artists); $i++) {
    $folder_name = strtolower($artists[$i][0]);
    for ($k = 0; $k < count($folder_fix); $k++) {
        $folder_name = str_replace($folder_fix[$k][0], $folder_fix[$k][1], $folder_name);
    }
    array_push($artists[$i], $folder_name);
}

Later, I add the album and track count for each artist to the array:

$lyrics_base = "lyrics/";
for ($i = 0; $i < count($artists); $i++) {
    $albums_path    = $lyrics_base . $artists[$i][1] . "/*";
    $tracks_path    = $lyrics_base . $artists[$i][1] . "/*/*";
    $albums         = count(glob($albums_path));
    $tracks         = count(glob($tracks_path));
    array_push($artists[$i], $albums);
    array_push($artists[$i], $tracks);
}

The end result of the array looks like this:

$artists = [
    [ "Avril Lavigne",  "avril_lavigne",    5,  61  ],
    [ "3 Doors Down",   "3_doors_down",     5,  13  ],
    [ "Celine Dion",    "celine_dion",      7,  22  ],
    [ "Evanescence",    "evanescence",      4,  10  ],
    [ "Shania Twain",   "shania_twain",     3,  12  ],
    [ "Green Day",      "green_day",        8,  26  ],
    //...
];

Now, my problem is that this process happens every time I visit the page. The 2nd, 3rd, and the 4th columns are created again and again. I think this is redundant.

I want to save the end result of the array and use it on the page. If this was JavaScript I'd use JSON.stringify(), but in PHP I don't know how to get the end result of the array. print_r() doesn't do the job, because it prints it like this:

Array
(
    [0] => Array
        (
            [0] => Avril Lavigne
            [1] => avril_lavigne
            [2] => 5
            [3] => 61
        )

    [1] => Array
        (
            [0] => 3 Doors Down
            [1] => 3_doors_down
            [2] => 5
            [3] => 13
        )
...

I want it like this:

[
    [
        "Avril Lavigne",
        "avril_lavigne",
        5,
        61
    ],
    [
        "3 Doors Down",
        "3_doors_down",
        5,
        13
    ],
    //...
]

Is there a way to print the array the JSON.stringify() way?

Answer 1

Is this what you want?

echo json_encode($artists)

PHP: json_encode

Answer 2

You can use this simple function from my CMS EFFCORE:

function data_stringify($data) {
  switch (gettype($data)) {
    case 'string' : return '\''.addcslashes($data, "'\\").'\'';
    case 'boolean': return $data ? 'true' : 'false';
    case 'NULL'   : return 'null';
    case 'object' :
    case 'array'  :
      $expressions = [];
      foreach ($data as $c_key => $c_value) {
        $expressions[] = data_stringify($c_key).' => '.
                         data_stringify($c_value);
      }
      return gettype($data) === 'object' ?
        '(object)['.implode(', ', $expressions).']' :
                '['.implode(', ', $expressions).']';
    default: return (string)$data;
  }
}

TEST

var_dump( data_stringify(-1    ) === '-1'     );
var_dump( data_stringify(-1.1  ) === '-1.1'   );
var_dump( data_stringify(123e1 ) === '1230'   ); # exponential notation
var_dump( data_stringify(0x123 ) === '291'    ); # hexadecimal notation
var_dump( data_stringify(01234 ) === '668'    ); # octal notation
var_dump( data_stringify(0b101 ) === '5'      ); # binary notation
var_dump( data_stringify('?123') === "'?123'" );
var_dump( data_stringify('123?') === "'123?'" );
var_dump( data_stringify(true  ) === 'true'   );
var_dump( data_stringify(false ) === 'false'  );
var_dump( data_stringify(null  ) === 'null'   );

array

var_dump(
  data_stringify([
    100,
   '200',
   'item3' =>  300,
   'item4' => '400',
   'item5' => 'value500'
  ]) === "[".
   "0 => 100, ".
   "1 => '200', ".
   "'item3' => 300, ".
   "'item4' => '400', ".
   "'item5' => 'value500']"
);

object

var_dump(
  data_stringify((object)[
    'prop1' =>  100,
    'prop2' => '200',
    'prop3' => 'value300'
  ]) === "(object)[".
   "'prop1' => 100, ".
   "'prop2' => '200', ".
   "'prop3' => 'value300']"
);

array with object

var_dump(
  data_stringify([
    100,
   '200',
   'item3' => (object)['prop1' =>  1, 'prop2' => '2', 'prop3' => 'value3'],
   'item4' => '400',
   'item5' => 'value500'
  ]) === "[".
   "0 => 100, ".
   "1 => '200', ".
   "'item3' => (object)['prop1' => 1, 'prop2' => '2', 'prop3' => 'value3'], ".
   "'item4' => '400', ".
   "'item5' => 'value500']"
);

object with array

var_dump(
  data_stringify((object)[
    'prop1' =>  1,
    'prop2' => '2',
    'prop3' => [100, '200', 'item3' => '300', 'item4' => 'value400'],
    'prop4' => 'value4'
  ]) === "(object)[".
   "'prop1' => 1, ".
   "'prop2' => '2', ".
   "'prop3' => [0 => 100, 1 => '200', 'item3' => '300', 'item4' => 'value400'], ".
   "'prop4' => 'value4']"
);