PHP Array – Insert item before/after array index

 

<?php

class Arr

{

/**

* Inserts values before specific key.

*

* @param array $array

* @param sting/integer $position

* @param array $values

* @throws Exception

*/

public static function insert_before(array &$array, $position, array $values)

{

// enforce existing position

if (!isset($array[$position]))

{

throw new Exception(strtr('Array position does not exist (:1)', [':1' => $position]));

}

// offset

$offset = -1;

// loop through array

foreach ($array as $key => $value)

{

// increase offset

++$offset;

// break if key has been found

if ($key == $position)

{

break;

}

}

$array = array_slice($array, 0, $offset, TRUE) + $values + array_slice($array, $offset, NULL, TRUE);

return $array;

}

/**

* Inserts values after specific key.

*

* @param array $array

* @param sting/integer $position

* @param array $values

* @throws Exception

*/

public static function insert_after(array &$array, $position, array $values)

{

// enforce existing position

if (!isset($array[$position]))

{

throw new Exception(strtr('Array position does not exist (:1)', [':1' => $position]));

}

// offset

$offset = 0;

// loop through array

foreach ($array as $key => $value)

{

// increase offset

++$offset;

// break if key has been found

if ($key == $position)

{

break;

}

}

$array = array_slice($array, 0, $offset, TRUE) + $values + array_slice($array, $offset, NULL, TRUE);

return $array;

}

}

// test array

$array_one = array(

'key1' => 'value1',

'key2' => 'value2',

'key3' => 'value3',

'key4' => 'value4',

'key5' => 'value5'

);

// try to insert value before

try

{

Arr::insert_before($array_one, 'key2', array('new_key1' => 'new_value1'));

}

catch (Exception $e)

{

echo strtr('Exception: Array could not be added before :1', array(':1' => 'key2')) . PHP_EOL;

}

// try to insert value after

try

{

Arr::insert_after($array_one, 'key4', array('new_key2' => 'new_value2'));

}

catch (Exception $e)

{

echo strtr('Exception: Array could not be added after :1', array(':1' => 'key4')) . PHP_EOL;

}

// print array

var_dump($array_one);

?>