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array_change_key_case> <Arrays
Last updated: Fri, 05 Sep 2008

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Array Functions

Table of Contents

  • array_change_key_case — Changes all keys in an array
  • array_chunk — Split an array into chunks
  • array_combine — Creates an array by using one array for keys and another for its values
  • array_count_values — Counts all the values of an array
  • array_diff_assoc — Computes the difference of arrays with additional index check
  • array_diff_key — Computes the difference of arrays using keys for comparison
  • array_diff_uassoc — Computes the difference of arrays with additional index check which is performed by a user supplied callback function
  • array_diff_ukey — Computes the difference of arrays using a callback function on the keys for comparison
  • array_diff — Computes the difference of arrays
  • array_fill_keys — Fill an array with values, specifying keys
  • array_fill — Fill an array with values
  • array_filter — Filters elements of an array using a callback function
  • array_flip — Exchanges all keys with their associated values in an array
  • array_intersect_assoc — Computes the intersection of arrays with additional index check
  • array_intersect_key — Computes the intersection of arrays using keys for comparison
  • array_intersect_uassoc — Computes the intersection of arrays with additional index check, compares indexes by a callback function
  • array_intersect_ukey — Computes the intersection of arrays using a callback function on the keys for comparison
  • array_intersect — Computes the intersection of arrays
  • array_key_exists — Checks if the given key or index exists in the array
  • array_keys — Return all the keys of an array
  • array_map — Applies the callback to the elements of the given arrays
  • array_merge_recursive — Merge two or more arrays recursively
  • array_merge — Merge one or more arrays
  • array_multisort — Sort multiple or multi-dimensional arrays
  • array_pad — Pad array to the specified length with a value
  • array_pop — Pop the element off the end of array
  • array_product — Calculate the product of values in an array
  • array_push — Push one or more elements onto the end of array
  • array_rand — Pick one or more random entries out of an array
  • array_reduce — Iteratively reduce the array to a single value using a callback function
  • array_reverse — Return an array with elements in reverse order
  • array_search — Searches the array for a given value and returns the corresponding key if successful
  • array_shift — Shift an element off the beginning of array
  • array_slice — Extract a slice of the array
  • array_splice — Remove a portion of the array and replace it with something else
  • array_sum — Calculate the sum of values in an array
  • array_udiff_assoc — Computes the difference of arrays with additional index check, compares data by a callback function
  • array_udiff_uassoc — Computes the difference of arrays with additional index check, compares data and indexes by a callback function
  • array_udiff — Computes the difference of arrays by using a callback function for data comparison
  • array_uintersect_assoc — Computes the intersection of arrays with additional index check, compares data by a callback function
  • array_uintersect_uassoc — Computes the intersection of arrays with additional index check, compares data and indexes by a callback functions
  • array_uintersect — Computes the intersection of arrays, compares data by a callback function
  • array_unique — Removes duplicate values from an array
  • array_unshift — Prepend one or more elements to the beginning of an array
  • array_values — Return all the values of an array
  • array_walk_recursive — Apply a user function recursively to every member of an array
  • array_walk — Apply a user function to every member of an array
  • array — Create an array
  • arsort — Sort an array in reverse order and maintain index association
  • asort — Sort an array and maintain index association
  • compact — Create array containing variables and their values
  • count — Count elements in an array, or properties in an object
  • current — Return the current element in an array
  • each — Return the current key and value pair from an array and advance the array cursor
  • end — Set the internal pointer of an array to its last element
  • extract — Import variables into the current symbol table from an array
  • in_array — Checks if a value exists in an array
  • key — Fetch a key from an array
  • krsort — Sort an array by key in reverse order
  • ksort — Sort an array by key
  • list — Assign variables as if they were an array
  • natcasesort — Sort an array using a case insensitive "natural order" algorithm
  • natsort — Sort an array using a "natural order" algorithm
  • next — Advance the internal array pointer of an array
  • pos — Alias of current
  • prev — Rewind the internal array pointer
  • range — Create an array containing a range of elements
  • reset — Set the internal pointer of an array to its first element
  • rsort — Sort an array in reverse order
  • shuffle — Shuffle an array
  • sizeof — Alias of count
  • sort — Sort an array
  • uasort — Sort an array with a user-defined comparison function and maintain index association
  • uksort — Sort an array by keys using a user-defined comparison function
  • usort — Sort an array by values using a user-defined comparison function


array_change_key_case> <Arrays
Last updated: Fri, 05 Sep 2008
 
add a note add a note User Contributed Notes
Array Functions
pragash_jey at yahoo dot com
06-Apr-2008 10:38
Java Like Array Implementation!

<?php
/*
 * Author : Pragash Jeyaratnam
 * Vector Class
 * PHP Version 5.2.5
 * Contact : pragash_jey@yahoo.com.
 */
class Vector
{
    /*
     * The number of valid components in this Vector object.
     */
    protected $elementCount;
    /*
     * The array buffer into which the components of the vector are stored.
     */
    protected $elementData;
   
   
         
    /**Default vector Constructor*/
    function __construct()
    {
        $this->elementData = array();
        $this->elementCount = count($this->elementData);
    }
   
   
   
    /**Append the parameter element to the vector*/
    public function add($object)
    {
        if(!empty($object))
        {
            $this->elementData[] = $object;
            $this->elementCount = count($this->elementData);
            return true;
        }
        else
            return false;
           
    }
   
    /*
     * Returns true of Vector is empty false otherwise
     */
    public function isEmpty()
    {
        return($this->elementCount==0);
    }
   
   
  /*
   * Returns the current size of this Vector
   */
   public function size()
   {
       return $this->elementCount;
   }
   
   /*
    *  Searches for the first occurence of the given argument
    **/
   public function indexOf($object)
   {
          if(($index =array_search($object,$this->elementData)) !==false)
              return $index;
          else
              return -1;
   }
  
   /*
    * This function will retain TRUE if $object is contained
    * within the vector else FALSE
    */
  
   public function contains($object)
   {
           return ($this->indexOf($object)>=0);
   }
   
   /*
    * Returns Vector Object at index $index
    * Error : Null is returned
    */
     
   public function get($index)
   {
           if($this->checkBound($index))
           {
               return ($this->elementData[$index]);
           }
           return NULL;
   }
  
   /*
    * Sets the object at $index to be $object
    **/
  
   public function set($index,$object)
   {
           if($this->checkBound($index))
           {
               $this->elementData[$index] =$object ;
               return true;
           }
           return false;
   }
  
  /*
   * Removes element at $index
   **/
  
      public function removeAt($index)
      {
       if ($this->checkBound($index))
           {
                 for ($i = $index; $i != $this->elementCount - 1; $i++)
                  {
                   $this->elementData[$i] = $this->elementData[$i +1];
             }
       array_pop($this->elementData);
       $this->elementCount = count($this->elementData);
           
       return true;
       }
       else {
            return false;
            }
      }
   
    /**
     * Removes all elements from the Vector.  Note that this does not
     * resize the internal data array.
     */
   public function removeAll()
   {
         if($this->elementCount ==0)
             return;
         for($i=0;$i<$this->size();$i++)
         {
             $this->set($i,NULL);
         }
   }
   
   
   /*
    * This function checks whether index
    * is within the array bound
    **/
  
   private function checkBound($index)
   {
         if($index > $this->elementCount-1 || $index < 0)
         {
             throw new Exception('Array Index Out Of Bound Exception');
             return false;
         }
         return true;
   }
  
    /*
     *Removes the first element from the Vector
     */
   
    public function removeFirstElement()
    {
        if($this->elementCount==0)
        {
            throw new Exception('No Such Element');
        }
        $test =array_shift($this->elementData);
        if(!empty($test))
            $this->elementCount = count($this->elementData);
    }
  
}
?>
Anonymous
29-Mar-2008 03:28
This is the shorter way to flatten a array:
<?php
  function array_flatten($a) {
    foreach($a as $k=>$v) $a[$k]=(array)$v;
    return call_user_func_array(array_merge,$a);
  }
?>
bas at muer dot nl
17-Mar-2008 12:17
I see a lot of people here writing complex functions to convert an array to a string, for use with Javascript or other things (possibly even databases, which would be bad).
For Javascript, the most efficient way would be JSON (http://www.php.net/json_encode). For normal use, serialize() (http://www.php.net/serialize) is your friend.
jake at blah dot inf
06-Mar-2008 09:03
@margol:

<?php
$tuple_array = array(array('key1' => 'val1'), array('key2' => 'val2'));
list($key, $val) = each(array_pop($tuple_array));
?>

But, why not use a two element array instead of a single-element associative array?

<?php
$tuple_array = array(array('key1', 'val1'), array('key2','val2'));
list($key,$val) = array_pop($tuple_array);
?>
margol at beamartyr dot net
04-Mar-2008 04:45
More intuitive tuple support would be nice  :)

But for those scratching their heads, like I did, to extract a tuple from an array of tuples, do something like:

    $tuple = array_pop($tuple_array);
    $key = key($tuple);
    $val = $tuple[$key];
yousefomar (a) yahoo dot com
28-Feb-2008 02:26
Here is how you refresh the expiration time for multiple cookies:

// get the cookie names
$keys=array_keys($_COOKIE);

// loop through all the cookies and update the exp. time
for ($i=0; $i<count($_COOKIE);$i++)
   setcookie( $keys[$i], $_COOKIE[$keys[$i]], time()+3600);

you can use this in authentication validate file to keep the session up.
ms419 at freezone dot co dot uk
14-Feb-2008 01:35
This function takes an array, a key and a value. If the key is not an array, it acts just like $array[$key] =& $value; If the key is an array, it recurses in the array, creating nested arrays as necessary.

Example:

$array = array('A' => array('B' => 'phi'));
$key = array('A', 'Z');
$value = 'gamma';

arraySet($array, $key, $value);

$array should now be:

array('A' => array('B' => 'phi', 'C' => 'gamma'));

This is useful for constructing nested arrays from sets of filesystem paths (e.g. 'A/B/C') or structured variable names (e.g. 'A.B.C' or 'A[B][C]')

Example:

arraySet($array, preg_split('/\//', $path, -1, PREG_SPLIT_NO_EMPTY), $value);

function arraySet(array &$array, $key, &$value)
{
    if (is_array($key)) {
        $keyComponent = array_shift($key);

        if (empty($key)) {
            $array[$keyComponent] =& $value;
            return;
        }

        if (!is_array($array[$keyComponent])) {
            $array[$keyComponent] = array();
        }

        PHP_CodeSniffer_arraySet($array[$keyComponent], $key, $value);
        return;
    }

    $array[$key] =& $value;
}
dennis at DONTSPAMME dot born05 dot nl
13-Feb-2008 10:22
I haven't completely figured out when or why an array gets referenced or copied, but it gave me quite the headache..

So i wrote a function which recursively copies an array while preserving keys and also clones objects if encountered

<?php
    /**
     * make a recursive copy of an array
     *
     * @param array $aSource
     * @return array    copy of source array
     */
    function array_copy ($aSource) {
        // check if input is really an array
        if (!is_array($aSource)) {
            throw new Exception("Input is not an Array");
        }
       
        // initialize return array
        $aRetAr = array();
       
        // get array keys
        $aKeys = array_keys($aSource);
        // get array values
        $aVals = array_values($aSource);
       
        // loop through array and assign keys+values to new return array
        for ($x=0;$x<count($aKeys);$x++) {
            // clone if object
            if (is_object($aVals[$x])) {
                $aRetAr[$aKeys[$x]]=clone $aVals[$x];
            // recursively add array
            } elseif (is_array($aVals[$x])) {
                $aRetAr[$aKeys[$x]]=array_copy ($aVals[$x]);
            // assign just a plain scalar value
            } else {
                $aRetAr[$aKeys[$x]]=$aVals[$x];
            }
        }
       
        return $aRetAr;
    }
?>

I hope i can save someone else's aspirine with this ;)
csorfab at gmail dot com
06-Feb-2008 01:26
Here's a function I wrote to combine the values in an array in all different ways, and which returns a two-dimensional array as a byref result.

E.g.

if called:
comb(array(1, 2, 3), $r);

then $r would be:

1 2 3
1 3 2
2 1 3
2 3 1
3 1 2
3 2 1

<?php

    function comb($arr, &$rarr, $vtemp = array()){   
        foreach($arr as $key => $value){
            $vtemp2 = $vtemp;
            $vtemp2[] = $value;

            $atemp = $arr;           
            unset($atemp[$key]);
           
            if(count($atemp) > 0){
                comb($atemp, $rarr, $vtemp2);
            } else {
                $t = array();
           
                foreach($vtemp2 as $val){
                    $t[] = $val;
                }
               
                $rarr[] = $t;
            }
        }
    }

?>
christian dot reinecke at web dot de
02-Feb-2008 04:12
Here are two more functions handling string2array and access array by string. It's useful if you want to access an array in xpath-style, such as parse_ini_file return values with $process_sections = TRUE.

<?php
function createArrayByString($string, $separator, $value = NULL)
{
    if (strlen($string) > 0) {
        $splitter = explode($separator, $string);
        $index = array_shift($splitter); // get first element
        $function = __FUNCTION__;
        return array($index => $function(implode($separator, $splitter), $separator, $value));
    }
    return $value;
}

function accessArrayByString($array, $string, $separator, $default = NULL)
{
    if (!is_array($array)) {
        return empty($string) ? $array : $default;
    }
    @list ($key, $rest) = explode($separator, $string, 2); // @ needed for last access
   
    $function = __FUNCTION__;
    return array_key_exists($key, $array)
         ? $function($array[$key], $rest, $separator, $default)
         : $default;
}

$string = "one.two.three.four";
$separator = ".";

$array = createArrayByString($string, $separator, "standard value");
$return = accessArrayByString($array, $string, $separator, "element not found");

var_dump($array); // should return array("one" => array("two" => array("three" => array("four" => "standard value"))))
var_dump($return); // should return "standard value";
?>

change the function name to what ever you want, the recursive call uses __FUNCTION__ for re-call.
florian at egliselasauzaie dot fr
30-Jan-2008 05:09
I've created a class which is comparable to a Vector in C++;
<?php
class Vector {
    public $nb_elements;
    public $liste;

    public function Vector() {
        $this->liste = array ();
        $this->nb_elements = count($this->liste);
    }

    public function push_back($valeur) {
        if (!empty ($valeur)) {
            $this->liste[] = $valeur;
            $this->nb_elements = count($this->liste);
            return true;
        } else {
            return false;
        }
    }
    public function insert_at($indice, $valeur) {
        if ($indice > 0 && $indice < $this->nb_elements) {
            for ($i = $this->nb_elements; $i != $indice; $i--) {
                $this->liste[$i] = $this->liste[$i -1];
            }
            $this->liste[$indice] = $valeur;
            $this->nb_elements = count($this->liste);
            return true;
        } else {
            return false;
        }
    }
    public function remove_at($indice) {
        if ($indice > 0 && $indice < $this->nb_elements) {
            for ($i = $indice; $i != $this->nb_elements - 1; $i++) {
                $this->liste[$i] = $this->liste[$i +1];
            }
            array_pop($this->liste);
            $this->nb_elements = count($this->liste);
            return true;
        } else {
            return false;
        }
    }
    public function pop() {
        $value = array_pop($this->liste);
        $this->nb_elements = count($this->liste);
        return $value;
    }
    public function shift() {
        $value = array_shift($this->liste);
        $this->nb_elements = count($this->liste);
        return true;
    }
}
?>
really quick function
25-Jan-2008 03:37
function array_flatten($a){ //flattens multi-dim arrays (distroys keys)
    $ab = array(); if(!is_array($a)) return $ab;
    foreach($a as $value){
        if(is_array($value)){
            $ab = array_merge($ab,array_flatten($value));
        }else{
            array_push($ab,$value);
        }
    }
    return $ab;
}
Jck_true (leave out the &#39;_&#39; at gmail dot com)
25-Jan-2008 05:00
A usefull function that returns a flat array.
I use it in a template system. Let the user pass a multidimensional array. Convert it using my function. Then use
<?php
$array = flatten($array,'','{$','}','->');
echo str_replace(array_keys($array),array_values($array),$template)
/**
* Flattens out an multidimension array
* Using the last parameters you can define the new key based on the old path.
* @param array $array A multidimension array
* @param string $prefix Internal perfix parameter - leave empty.
* @param string $start_string What string should start the final array key?
* @param string $end_string What string should end the final array key?
* @param string $seperator The string that should seperate the piecies in final array key path
* @return array Returns the flat array
*/
function flatten($array, $start_string= '{$',$end_string= '}',$seperator='->',$prefix="") {
  $return = array();
  foreach($array as $key=>$value) {
    if (is_array($value)) {
      $return = array_merge($return, Parser_method_replace::flatten($value, $prefix.$key.$seperator,$start_string,$end_string,$seperator));
    } else
      $return [$start_string.$prefix.$key.$end_string] = $value;
  }
  return $return;
}
}
?>
Example:
$template = 'My string with replacement {$test->subkey}';
{$test->subkey} will get replaced with $array['test']['subkey']
chaos dot global dot net at gmail dot com
02-Jan-2008 06:53
if some one will need to convert array to php code use this function:

DEFINE('OFFSET_DELIMETER', "\t");

function array2php($array, $offset = OFFSET_DELIMETER)  {
    $text = '';
    foreach($array as $k => $v) {
        if (is_array($v)) {
            $text .= "{$offset}'{$k}' => array(\n".array2php($v, $offset.OFFSET_DELIMETER)."$offset)";
        } else {
            $text .= "{$offset}'{$k}' => ".(is_string($v)? "'$v'": $v);
        }
        $text .= ",\n";
    }
    if ($len = strlen($text)) $text[$len - 2] = " ";
    return $text;
}
Hayley Watson
17-Oct-2007 07:10
Regarding cyberchrist at futura dot net's function. It makes an unnecessary array_merge(); the elements of $b that are merged with those of $a are immediately removed again by the array_diff(). The "limiting to known values" is entirely unnecessary, in other words: arrays already only contain "known values".

Also, the description and function only address the issue of whether $a is a subset of $b, not whether it is a proper subset. For $a to be a proper subset of $b, it must also be the case that $b is not a subset of $a.

Taking those points into account (and a personal aesthetic dislike of "if(test) return true; else return false;" gives:

<?php
function is_subset($a, $b)
{
    return count(array_diff($a,$b))==0;
}

function is_proper_subset($a, $b)
{
    return is_subset($a, $b) && !is_subset($b, $a);
}
?>
cyberchrist at futura dot net
15-Oct-2007 09:33
Lately, dealing with databases, I've been finding myself needing to know if one array, $a, is a proper subset of $b.

Mathematically, this is asking (in set theory) [excuse the use of u and n instead of proper Unicode):
 
( A u B ) n ( ~ B )

What this does is it first limits to known values, then looks for anything outside of B but in the union of A and B (which would be those things in A which are not also in B).

If any value exists in this set, then A is NOT a proper subset of B, because a value exists in A but not in B.  For A to be a proper subset, all values in A must be in B.

I'm sure this could easily be done any number of ways but this seems to work for me.  It's not got a lot of error detection such as sterilizing inputs or checking input types.

// bool array_subset( array, array )
// Returns true if $a is a proper subset of $b, returns false otherwise.

function array_subset( $a, $b )
{
    if( count( array_diff( array_merge($a,$b), $b)) == 0 )
        return true;
    else
        return false;
}
Kazuyoshi Tlacaelel
30-Aug-2007 02:56
<?php
/**
 * converts a multidimensional array to a flat array
 *
 * trying to keep the original names of the keys
 * if repeated keys are found a hash will be added to the
 * keys trying to keep as much as possible of the original
 * key context
 *
 * september 30 2007
 *
 * PHP version 5
 *
 * @license         GPL
 *
 */

$array = array ( 0 => array ( 0 => 1, 1 => 2, 2 => array ( 0 => 3, 1 => 4, 2 =>
array ( 0 => 5, 1 => 6, 2 => array ( 0 => 7, 1 => 8,),),), 3 => array (
    0 => array ( 0 => 9, 1 => 10, 2 => array ( 0 => 11, 1 => 12,
    2 => array ( 0 => 13, 1 => 14, 2 => array ( 0 => 15, 1 => 16,),),),),
    1 => array ( 0 => 17, 1 => 18,),),), 1 => array ( 0 => 19, 1 => 20,),
    2 => array ( 0 => array ( 0 => 21, 1 => 22, 2 => array ( 0 => 23, 1 => 24,
    2 => array ( 0 => 25, 1 => 26, 2 => array ( 0 => 27, 1 => 28,),),),),
    1 => array ( 0 => 29, 1 => 30,),),);

/**
 * transforms a multidimensional array to a flat array
 *
 * the parameter is referenced
 * so no returning value is needed
 * @param array $array the multidimensional array to flat
 * @return void
 */
function array_flatten(&$array)
{
    function has_arrays($array)
    {
        foreach ($array as $item) {
            if (is_array($item)) {
                return true;
            }
        }
        return false;
    }

    function copy_array(&$array, $array_key)
    {
        $array2 = $array[$array_key];
        unset($array[$array_key]);
        foreach ($array2 as $subkey => $subvalue) {
            if (array_key_exists($subkey, $array)) {
                $array[generate_unique_key($subkey)] = $subvalue;
            } else {
                $array[$subkey] = $subvalue;
            }
        }
    }

    function generate_unique_key($key)
    {
        if (strlen($key)>8) {
            $key = $key[0] . $key[1] . $key[2];
        }
        $id = $key . '_';
        $uid = uniqid();
        $len = strlen($uid);
        $max = (9 - strlen($key));
        for ($c = $len; ; $c --) {
            $id .= $uid[$c];
            if ($c == ($len - $max)) {
                break;
            }
        }
        return $id;
    }

    function get_array_indexes($array)
    {
        $ret_array = array();
        foreach ($array as $key => $value) {
            if (is_array($value)) {
                $ret_array[] = $key;
            }
        }
        return $ret_array;
    }

    while(has_arrays($array)) {
        foreach (get_array_indexes($array) as $key) {
            copy_array($array, $key);
        }
    }
}

    array_flatten($array);
    array_multisort($array);
    var_export($array);

    /**
     *  OUTPUT
     *
     *  array (
     *    0 => 1,
     *    '1_403767b6' => 2,
     *    '0_793767b6' => 3,
     *    '1_8a3767b6' => 4,
     *    '0_454767b6' => 5,
     *    '1_564767b6' => 6,
     *    '0_035767b6' => 7,
     *    '1_345767b6' => 8,
     *    '0_e74767b6' => 9,
     *    '1_f84767b6' => 10,
     *    '0_855767b6' => 11,
     *    '1_a65767b6' => 12,
     *    '0_4e5767b6' => 13,
     *    '1_6f5767b6' => 14,
     *    '0_566767b6' => 15,
     *    '1_876767b6' => 16,
     *    '0_5b4767b6' => 17,
     *    '1_6c4767b6' => 18,
     *    '0_d43767b6' => 19,
     *    1 => 20,
     *    '0_4e3767b6' => 21,
     *    '1_5f3767b6' => 22,
     *    '0_ad4767b6' => 23,
     *    '1_ce4767b6' => 24,
     *    '0_485767b6' => 25,
     *    '1_695767b6' => 26,
     *    '0_116767b6' => 27,
     *    '1_426767b6' => 28,
     *    '0_814767b6' => 29,
     *    '1_924767b6' => 30,
     *  )
     */
?>
mo dot longman at gmail dot com
31-Jul-2007 02:27
to 2g4wx3:
i think better way for this is using JSON, if you have such module in your PHP. See json.org.

to convert JS array to JSON string: arr.toJSONString();
to convert JSON string to PHP array: json_decode($jsonString);

You can also stringify objects, numbers, etc.
g4wx3
19-Jul-2007 05:16
I needed a function to convert a php array into a javascript array.
No problem i found it on "the net".

But the function i found wasn't good enough, instead of return a string with javascript-array it echoed directly everything.
I wanted to write the string to a file, when calling the function out of my function libary.

Secondly, there where minor "bugs" in the script, when you're original array contained characters like line breaks(\r\n,..), or quotes('), it would hack up the javascript array

Sow, i changed the function and fixed the bug.

<?php
//SUPER COOL : http://www.communitymx.com/content/article.cfm?page=3&cid=7CD16
//Checkout:  REVERSE: http://www.hscripts.com/tutorials/php/jsArrayToPHP.php
//Convert a PHP array to a JavaScript one (rev. 4)
//Changlog by g4wx3: echo replaced by $output, added function output
function output($string) //make javascript ready
    {
    $string = str_replace( array( '\\' , '\'' ), array('\\\\', '\\\'') , $string); //-> for javascript array
    $string = str_replace(  array("\r\n", "\r", "\n") , '<br>' , $string);    //nl2br
    return $string;
    }
function arrayToJS4($array, $baseName ) {
    //Write out the initial array definition
//v4    echo ($baseName . " = new Array(); \r\n ");
    $output = $baseName . " = new Array(); \r\n ";

    //Reset the array loop pointer
    reset ($array);

    //Use list() and each() to loop over each key/value
    //pair of the array
    while (list($key, $value) = each($array)) {
        if (is_numeric($key)) {
        //A numeric key, so output as usual
        $outKey = "[" . $key . "]";
        } else {
        //A string key, so output as a string
        $outKey = "['" . $key . "']";
        }
     
        if (is_array($value)) {
        //The value is another array, so simply call
        //another instance of this function to handle it
        $output .= arrayToJS4($value, $baseName . $outKey);
        } else {

            //Output the key declaration
//v4            echo ($baseName . $outKey . " = ");     
            $output .= $baseName . $outKey . " = ";
           
            //Now output the value
            if (is_string($value)) {
                //Output as a string, as we did before      
//v4                echo ("'" . output($value) . "'; \r\n ");
                $output .= "'" . output($value) . "'; \r\n ";
            } else if ($value === false) {
                //Explicitly output false
//v4                echo ("false; \r\n");
                $output .= "false; \r\n";
            } else if ($value === NULL) {
                //Explicitly output null
//v4                echo ("null; \r\n");
                $output .= "null; \r\n";
            } else if ($value === true) {
                //Explicitly output true
//v4                echo ("true; \r\n");
                $output .= "true; \r\n";
            } else {
            //Output the value directly otherwise
//v4            echo ($value . "; \r\n");
            $output .= $value . "; \r\n";
            }
        }
    }
return $output;
}
?>
You can use this for printing $_GET array, for example
peanutpad at msn dot com
15-Jun-2007 06:15
heres a function from http://www.linksback.org  Feedback welcome, of course!  Public domain, yadda yadda.

function mySort(&$array,$key) {
    if (!is_array($array) || count($array) == 0) return true;
    $assocSortCompare  = '$a = $a["'.$key.'"]; $b = $b["'.$key.'"];';

    if (is_numeric($array[0][$key])) {
      $assocSortCompare.= ' return ($a == $b) ? 0 : (($a < $b) ? -1 : 1);';
    } else {
      $assocSortCompare.= ' return strcmp($a,$b);';
    }

    $assocSortCompare = create_function('$a,$b',$assocSortCompare);
    return usort($array,$assocSortCompare);
}
webdev at svbeatrix dot com
11-Jun-2007 12:06
Bugs happen, but how can people post functions that WON'T EVEN COMPILE!  I truly detest finding a cool code snippet or function and then having to debug them. Sorry for the rant, but I have experienced this scenario a number of times.  TEST YOUR CODE, THEN POST!

Here is a revised and corrected previously posted function ArrayDepth, which had 3 bugs and yes, would not compile.

function ArrayDepth($Array,$DepthCount=-1) {
// Find maximum depth of an array
// Usage: int ArrayDepth( array $array )
// returns integer with max depth
// if Array is a string or an empty array it will return 0
  $DepthArray=array(0);
  $DepthCount++;
  $Depth = 0;
  if (is_array($Array))
    foreach ($Array as $Key => $Value) {
      $DepthArray[]=ArrayDepth($Value,$DepthCount);
    }
  else
    return $DepthCount;
  return max($DepthCount,max($DepthArray));
}
sid dot pasquale at gmail dot com
29-May-2007 05:57
<?php
/* This function allow you to transform a multidimensional array
   in a simple monodimensional array.
   Usage: array_walk($oldarray, 'flatten_array', &$newarray);
   For example, this code below shows to you:
        Array
        (
            [1] => Array
                (
                    [0] => 1
                    [1] => 2
                )
       
            [2] => Array
                (
                    [0] => 3
                    [1] => 4
                )
       
        )
       
        Array
        (
            [0] => 1
            [1] => 2
            [2] => 3
            [3] => 4
        )
*/

function flatten_array($value, $key, &$array) {
    if (!is_array($value))
        array_push($array,$value);
    else
        array_walk($value, 'flatten_array', &$array);
 
}
 
$oldarray = array(
    1 => array(1,2),
    2 => array(3,4)
);
$newarray = array();
array_walk($oldarray, 'flatten_array', &$newarray);
echo "<pre>";
print_r($oldarray);
print_r($newarray);
echo "</pre>";
?>
info at dyflexis dot nl
17-Apr-2007 04:13
A modernized version of the flatten_array() functies written by

davidj at boundlessgallery dot DISLIKESPAM dot com
on 02-Apr-2004 03:10

This function is able to work with associative arrays

<?php
function flatten_array($array) {
     $size=sizeof($array);
     $keys=array_keys($array);
    for($x = 0; $x < $size; $x++) {
         $element = $array[$keys[$x]];

        if(is_array($element)) {
            $results = flatten_array($element);
                $sr = sizeof($results);
                $sk=array_keys($results);
            for($y = 0; $y < $sr; $y++) {
                $flat_array[$sk[$y]] = $results[$sk[$y]];
            }
        } else {
            $flat_array[$keys[$x]] = $element;
        }
    }

    return $flat_array;
}
?>
info at joolee dot nl
19-Mar-2007 08:49
A slight modification in the arraytostring function, posted below. This function lists an array the same way you would define it in PHP.

<?PHP
function arraytostring($array, $depth = 0)
{
   if($depth > 0)
      $tab = implode('', array_fill(0, $depth, "\t"));
   $text.="array(\n";
   $count=count($array);

   foreach ($array as $key=>$value)
   {
       $x++;

       if (is_array($value))
       {
           if(substr($text,-1,1)==')')    $text .= ',';
           $text.=$tab."\t".'"'.$key.'"'." => ".arraytostring($value, $depth+1);
           continue;
       }

       $text.=$tab."\t"."\"$key\" => \"$value\"";

       if ($count!=$x) $text.=",\n";
   }

   $text.="\n".$tab.")\n";

   if(substr($text, -4, 4)=='),),')$text.='))';

   return $text;
}
?>
Vladson
14-Mar-2007 11:18
Hope someone find it useful..

<?php
/*
    Function: eratosthenes
    Usage: array eratosthenes ( int max_value )

    Description:
    Sieve of Eratosthenes is a simple, ancient algorithm
    for finding all prime numbers up to a specified integer.
    It was created by Eratosthenes, an ancient Greek mathematician.
*/
function eratosthenes($max) {
    $sieve = array_fill(2, ($max-1), false);
    while ($key = array_search(false, $sieve)) {
        $sieve[$key] = true;
        for ($i=$key*$key; $i<=$max; $i+=$key) {
            if (array_key_exists($i, $sieve)) {
                unset($sieve[$i]);
            }
        }
    }
    return array_keys($sieve);
}
?>
aflavio at gmail dot com
01-Mar-2007 02:29
/**
    * Remove a value from a array
    * @param string $val
    * @param array $arr
    * @return array $array_remval
    */
    function array_remval($val, &$arr)
    {
          $array_remval = $arr;
          for($x=0;$x<count($array_remval)-1;$x++)
          {
              $i=array_search($val,$array_remval);
              if($i===false)return false;
              $array_remval=array_merge(array_slice($array_remval, 0,$i), array_slice($array_remval, $i+1));
          }
          return $array_remval;
    }

$stack = array("orange", "banana", "apple", "raspberry", "apple");

output $stack = array("orange", "banana", "raspberry");
rune at zedeler dot dk
27-Feb-2007 11:42
Notice that keys are considered equal if they are "=="-equal. That is:

<?
$a = array();
$a[1] = 'this is the first value';
$a[true] = 'this value overrides the first value';
$a['1'] = 'so does this one';
?>
Mark Lindeman
17-Jan-2007 05:10
Very simple solution for changing the key of an associative array, of course it will fail in a lot of scenarios, but will do the trick in simple arrays:

<?php
function replace_key(&$input, $from_key, $to_key)
{
    $input = unserialize(str_replace(':"'.$from_key.'";', ':"'.$to_key.'";',serialize($input)));
}

$array =array("a"=>1,