ConFoo 2025

current

(PHP 4, PHP 5, PHP 7, PHP 8)

currentRestituisce l'elemento corrente di un array

Descrizione

current(array $array): mixed

Ogni array ha un puntatore interno all'elemento "corrente", che è inizializzato al primo elemento inserito nell'array.

La funzione current() restituisce il valore dell'elemento che è attualmente puntato dal puntatore interno. In ogni caso non muove il puntatore. Se il puntatore interno punta oltre la fine della lista di elementi, current() restituisce false.

Avviso

Se l'array contiene elementi vuoti (0 o "", la stringa vuota) la funzione restituirà false pure per questi elementi. Questo rende impossibile stabilire se si è veramente alla fine della lista in un array di questo tipo usando current(). Per attraversare in modo corretto un array che può contenere elementi vuoti, usare la funzione each().

Example #1 Esempio di current() e funzioni relative

<?php
$trasporti
= array('piedi', 'bicicletta', 'automobile', 'aereo');
$mode = current($trasporti); // $mode = 'piedi';
$mode = next($trasporti); // $mode = 'bicicletta';
$mode = current($trasporti); // $mode = 'bicicletta';
$mode = prev($trasporti); // $mode = 'piedi';
$mode = end($trasporti); // $mode = 'aereo';
$mode = current($trasporti); // $mode = 'aereo';
?>

Vedere anche end(), key(), next(), prev() e reset().

add a note

User Contributed Notes 11 notes

up
20
michael at squiloople dot com
12 years ago
current() also works on objects:

<?php

echo current((object) array('one', 'two')); // Outputs: one

?>
up
7
sergey dot karavay at gmail dot com
3 years ago
It looks like `current()` is deprectated for calling on objects since PHP 7.4.

Consider this code

```
$a = new ArrayIterator([1,2,3]);

var_dump(current($a), $a->current());
```

It returns
```
int(1)
int(1)
```

In PHP 7.3, but in PHP7.4 you get:
```
bool(false)
int(1)
```

And in PHP8:
```
Deprecated: current(): Calling current() on an object is deprecated in /in/fdrNR on line 5
bool(false)
int(1)
```
up
9
vaclav dot sir at gmail dot com
17 years ago
To that "note": You won't be able to distinguish the end of an array from a boolean FALSE element, BUT you can distinguish the end from a NULL value of the key() function.

Example:
<?php
if (key($array) === null) {
echo
"You are in the end of the array.";
} else {
echo
"Current element: " . current($array);
}
?>
up
7
strate at yandex dot com
11 years ago
Note, that you can pass array by expression, not only by reference (as described in doc).

<?php
var_dump
( current( array(1,2,3) ) ); // (int) 1
?>
up
8
retestro_REMOVE at SPAM_esperanto dot org dot il
21 years ago
The docs do not specify this, but adding to the array using the brackets syntax:
<?php $my_array[] = $new_value; ?>
will not advance the internal pointer of the array. therefore, you cannot use current() to get the last value added or key() to get the key of the most recently added element.

You should do an end($my_array) to advance the internal pointer to the end ( as stated in one of the notes on end() ), then

<?php
$last_key
= key($my_array); // will return the key
$last_value = current($my_array); // will return the value
?>

If you have no need in the key, $last_value = end($my_array) will also do the job.

- Sergey.
up
6
mdeng at kabenresearch dot com
20 years ago
For large array(my sample was 80000+ elements), if you want to traverse the array in sequence, using array index $a[$i] could be very inefficient(very slow). I had to switch to use current($a).
up
5
Vasily Yudin (st-2 at mail dot ru)
10 years ago
If you do current() after using uset() on foreach statement, you can get FALSE in PHP version 5.2.4 and above.
There is example:
<?php
$prices
= array(
0 => '1300990',
1 => '500',
2 => '600'
);
foreach(
$prices as $key => $price){
if(
$price < 1000){
unset(
$prices[$key]);
}
}

var_dump(current($prices)); // bool(false)
?>
If you do unset() without foreach? all will be fine.
<?php
$prices
= array(
0 => '1300990',
1 => '500',
2 => '600'
);
unset(
$prices[1]);
unset(
$prices[2]);

var_dump(current($prices));
?>
up
1
leozmm at outlook dot com
5 years ago
Array can be passed by both REFERENCE and EXPRESSION on `current`, because current doesn't move array's internal pointer,
this is not true for other functions like: `end`, `next`, `prev` etc.

<?php
function foo() {return array(1,2,3);}
echo
current(foo()); // this print '1'
echo end(foo()); // this print error: Only variables should be passed by reference
?>
up
1
xedin dot unknown at gmail dot com
6 years ago
Array functions, such as `current()` and `rewind()` will work on `Traversable` as well, PHP 5.0 - 7.3, but not in HHVM:

<?php

$queue
= new ArrayIterator(array('adasdasd'));
reset($queue);
$current = current($queue);
var_dump($current);

?>

See https://3v4l.org/VjCHR
up
2
vitalib at 012 dot net dot il
21 years ago
Note that by copying an array its internal pointer is lost:

<?php
$myarray
= array(0=>'a', 1=>'b', 2=>'c');
next($myarray);
print_r(current($myarray));
echo
'<br>';
$a = $myarray;
print_r(current($a));
?>

Would output 'b' and then 'a' since the internal pointer wasn't copied. You can cope with that problem using references instead, like that:

<?php
$a
=& $myarray;
?>
up
0
pdarmis at gmail dot com
7 years ago
Based on this example http://php.net/manual/en/function.current.php#116128 i would like to add the following. As Vasily points out in his example
<?php
$prices
= array(
0 => '1300990',
1 => '500',
2 => '600'
);
foreach(
$prices as $key => $price){
if(
$price < 1000){
unset(
$prices[$key]);
}
}

var_dump(current($prices)); // bool(false)
?>
The above example will not work and return false for version of PHP between 5.2.4 and 5.6.29. The issue is not present on PHP versions >= 7.0.1
A different workaround (at least from Vasily's example) would be to use reset() before using current() in order to reset the array pointer to start.
<?php
$prices
= array(
0 => '1300990',
1 => '500',
2 => '600'
);
foreach(
$prices as $key => $price){
if(
$price < 1000){
unset(
$prices[$key]);
}
}
reset($prices);
var_dump(current($prices)); // string(7) "1300990"
?>
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