CODEWITHSUNDEEP
php
ihtus
ihtus

Reputation: 2811

Associative array - change position

For ex have this array:

[food] => Array (
    [fruits] => apple
    [vegetables] => garlic
    [nuts] => cashew
    [meat] => beaf
)

I need to change the position of a specific key-value combination.

Let's say I need to move [fruits] => apple to 3rd position

[food] => Array (
    [vegetables] => garlic
    [nuts] => cashew
    [fruits] => apple
    [meat] => beaf
)

I am not talking about sorting by key or value. I need to change position of key-value to a very strict new position.

Something like:

change_pos($my_arr, $key_to_move, $new_index);

=>

change_pos($my_arr, "fruits", 3);

Is that possible?

Upvotes: 6

Views: 11871

Answers (4)

Mehdikhody
Mehdikhody

Reputation: 1

/**
 * Moves an array item to a new index .
 *
 * @param array $array
 * @param int $from
 * @param int $to
 * @return void
 */
function array_move(array &$array, int $from, int $to)
{
    $item = array_splice($array, $from, 1);
    array_splice($array, $to, 0, $item);
}

/**
 * Moves an associative array item to a new index.
 * 
 * @param array $array
 * @param string $key
 * @param int $to
 * @return void
 */
function array_move_assoc(array &$array, string $key, int $to)
{
    if (!array_key_exists($key, $array)) return;

    $keys = array_keys($array);
    $values = array_values($array);
    $from = array_search($key, $keys);

    array_move($keys, $from, $to);
    array_move($values, $from, $to);

    $array = [];
    foreach ($keys as $index => $key) {
        $array[$key] = $values[$index];
    }
}

$array = [
    "fruits" => "apple",
    "vegetables" => "garlic", 
    "nuts" => "cashew", 
    "meat" => "beaf"
];

array_move_assoc($array, "fruits", 2);
print_r($array);

Array
(
    [vegetables] => garlic
    [nuts] => cashew
    [fruits] => apple
    [meat] => beaf
)

Upvotes: 0

ihtus
ihtus

Reputation: 2811

I would like to thank MIIB for his hard work! I will accept his answer for the hard work.

But I came up with a solution that fits me better and I will use it.

function ksort_arr (&$arr, $index_arr) {
    $arr_t=array();
    foreach($index_arr as $i=>$v) {
        foreach($arr as $k=>$b) {
            if ($k==$v) $arr_t[$k]=$b;
        }
    }
    $arr=$arr_t;
}

$arr=array("fruits"=>"apple","vegetables"=>"garlic","nuts"=>"cashew","meat"=>"beaf");
$index_arr=array("vegetables","meat","fruits","nuts");
ksort_arr($arr,$index_arr);
print_r($arr);

result

Array
(
    [vegetables] => garlic
    [meat] => beaf
    [fruits] => apple
    [nuts] => cashew
)

Upvotes: 3

Mike Starov
Mike Starov

Reputation: 7296

Here is a much simpler solution using a second array. It also provides some basic validation for new index parameter. Intended to be used with associative arrays only. It does not make sense to be used with numeric arrays.

function array_move($key, $new_index, $array)
{
    if($new_index < 0) return;
    if($new_index >= count($array)) return;
    if(!array_key_exists($key, $array)) return;

    $ret = array();
    $ind = 0;
    foreach($array as $k => $v)
    {
      if($new_index == $ind)
      {
        $ret[$key] = $array[$key];
        $ind++;
      }
      if($k != $key)
      {
        $ret[$k] = $v;
        $ind++;
      }
    }
    // one last check for end indexes
    if($new_index == $ind)
        $ret[$key] = $array[$key];


    return $ret;
}

Upvotes: 2

MIIB
MIIB

Reputation: 1849

It was hard , but finally:

<?php
function array_splice_assoc(&$input, $offset, $length, $replacement) {
        $replacement = (array) $replacement;
        $key_indices = array_flip(array_keys($input));
        if (isset($input[$offset]) && is_string($offset)) {
                $offset = $key_indices[$offset];
        }
        if (isset($input[$length]) && is_string($length)) {
                $length = $key_indices[$length] - $offset;
        }

        $input = array_slice($input, 0, $offset, TRUE)
                + $replacement
                + array_slice($input, $offset + $length, NULL, TRUE);
}
function array_move($which, $where, $array)
{
    $tmpWhich = $which;
    $j=0;
    $keys = array_keys($array);

    for($i=0;$i<count($array);$i++)
    {
        if($keys[$i]==$tmpWhich)
            $tmpWhich = $j;
        else
            $j++;
    }
    $tmp  = array_splice($array, $tmpWhich, 1);
    array_splice_assoc($array, $where, 0, $tmp);
    return $array;
}
$array = array('fruits' => 'apple','vegetables' => 'garlic','nuts' => 'cashew','meat' => 'beaf');
$res = array_move('vegetables',2,$array);
var_dump($res);
?>

Upvotes: 7

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