I have an array:
array( 4 => 'apple', 7 => 'orange', 13 => 'plum' )
I would like to get the first element of this array. Expected result: string apple
One requirement: it cannot be done with passing by reference, so array_shift
is not a good solution.
How can I do this?
6
40 Answers
Original answer, but costly (O(n)):
array_shift(array_values($array));
In O(1):
array_pop(array_reverse($array));
Other use cases, etc…
If modifying (in the sense of resetting array pointers) of $array
is not a problem, you might use:
reset($array);
This should be theoretically more efficient, if a array “copy” is needed:
array_shift(array_slice($array, 0, 1));
With PHP 5.4+ (but might cause an index error if empty):
array_values($array)[0];
32
+1 for the clever workaround to prevent modifying the original array with array_values()
– ChrisRI get this: <b>Strict Standards</b>: Only variables should be passed by reference. Nice workaround btw
– SimoneIsn’t this a little overkill? What if the array contains several thousands of elements? Is it justified to create a whole new array just to get its first element?
list()
andreset()
are much nicer solutions to my opinion.I agree. Total overkill and extraordinary resource heavy compared to one line which resets and returns the current value: reset($array);
– zmonteca-1 As the above commenters have said. It’s baffling to me that this has 101 upvotes.
As Mike pointed out (the easiest possible way):
$arr = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' )
echo reset($arr); // Echoes "apple"
If you want to get the key: (execute it after reset)
echo key($arr); // Echoes "4"
From PHP’s documentation:
mixed reset ( array &$array );
Description:
reset() rewinds array’s internal pointer to the first element and returns the value of the first array element, or FALSE if the array is
empty.
10
Although it is passed by reference to reset, the original array is not modified. I’m guessing that’s the reason hsz does not want to pass it by reference..?
The array’s iterator is modified. If you do this in a
foreach
with the subject array, you’ll screw it up.– Zenexer@Zenexer this is not always (usually) true. Usually in practise,
foreach
will copy the array which is it looping through.Neither @Zenexer nor Luke Cousins are right: 1) foreach does not use internat pointer of an array – instead it creates it’s own pointer. It is easy to check calling reset inside foreach – the loop will follow it’s way with no effect from
reset()
. 2) No, foreach DOES NOT create a copy of an array!!! It only creates it’s own pointer (not even a copy of an existing one – it is also easy to check, callingnext()
before foreach).– dmikam
$first_value = reset($array); // First element's value
$first_key = key($array); // First element's key
5
I haven’t actually tested it, but it seems this approach would be the most efficient.
– mason81Only problem is the question asked for the value, not the key. Thus current($array) should be used instead of of key($array)
– zmonteca@zmonteca $first_value = reset($array); here you get the value, reset() function rewinds arrays internal pointer and returns first element.
– S3Mithe best answer! was looking for key() equivalence to get the first value. This helps!
What if the array is empty?
reset()
will returnfalse
, which may lead to bugs if you expect the array to containbool
values.– Jacob
current($array)
returns the first element of an array, according to the PHP manual.
Every array has an internal pointer to its “current” element, which is initialized to the first element inserted into the array.
So it works until you have re-positioned the array pointer, and otherwise you’ll have to use reset()
which ll rewind array and ll return first element of array
According to the PHP manual reset.
reset() rewinds array’s internal pointer to the first element and returns the value of the first array element.
Examples of current()
and reset()
$array = array('step one', 'step two', 'step three', 'step four');
// by default, the pointer is on the first element
echo current($array) . "<br />n"; // "step one"
//Forward the array pointer and then reset it
// skip two steps
next($array);
next($array);
echo current($array) . "<br />n"; // "step three"
// reset pointer, start again on step one
echo reset($array) . "<br />n"; // "step one"
5
I don’t know why this wasn’t the accepted answer, as it answers the question fairly simply and accurately.
– relipsecurrent($array)
will only work if the array pointer is “currently” pointing to the first element, otherwisereset($array)
would be required.– JonIt seems
current()
no longer requires a reference, although the PHP docs do not reflect this. So I think this has become the best solution.– Ryan@Ryan agreed, but this solution was given 2 years prior to 2014 in this other answer of this same thread… Weird that this incomplete sentence got more upvotes.
What if the array is empty?
reset()
andcurrent()
will returnfalse
, which may lead to bugs if you expect the array to containbool
values.– Jacob
$arr = $array = array( 9 => 'apple', 7 => 'orange', 13 => 'plum' );
echo reset($arr); // echoes 'apple'
If you don’t want to lose the current pointer position, just create an alias for the array.
4
didn’t get it, what do you mean? It works fine whether the key of the first is bigger than the other ones.
– yoda+1 FYI
reset()
already returns the first element, so there is no need to usecurrent()
—echo reset($arr)
should suffice– Mike@Mike but you might prefer
current
toreset
to avoid PHP notice/error produced in reference cases, e.g.current(array_filter(...));
in 3v4l.What if the array is empty?
reset()
will returnfalse
, which may lead to bugs if you expect the array to containbool
values.– Jacob
You can get the Nth element with a language construct, “list”:
// First item
list($firstItem) = $yourArray;
// First item from an array that is returned from a function
list($firstItem) = functionThatReturnsArray();
// Second item
list( , $secondItem) = $yourArray;
With the array_keys
function you can do the same for keys:
list($firstKey) = array_keys($yourArray);
list(, $secondKey) = array_keys($yourArray);
8
This is exactly what I do:
list($first_value) = $my_array;
In my opinion, the very best option. It does not have the issues from the other answers presented here: no “overkill” because it does not copy or the array or create a new one. No “references”: the array is not modified. No “reset”: no changes to the array internal pointer…– J. BruniVery elegant solution, but throws an E_NOTICE when the array is empty.
– Tgr@Mike yes, but then it is not so elegant anymore 🙂
– TgrIsn’t this wrong?! It works only if array keys are
int
, try doinglist($firstItem) = array('key1' => 'value1');
and you will get an errorNotice: Undefined offset: 0
To clarify:
list($x) = foo();
is equivalent to$x = foo()[0];
. Note that this is not necessarily the same as “get the first item”, since even an integer-indexed array may not have an element with key 0. In my case I was doing “list($order) = get_order($user);” but “get_order” was returning orders keyed by their ID, which was usually not 0. As @Sergiy says, array_values() fixes this, but detracts from the efficiency and (more importantly) readability of the code.– Warbo
PHP 5.4+:
array_values($array)[0];
3
He edited his answer in Oct-2013 to include my answer that I added in April.
if the array is empty it will return
undefined key 0
so use it with caution
PHP 7.3 added two functions for getting the first and the last key of an array directly without modification of the original array and without creating any temporary objects:
Apart from being semantically meaningful, these functions don’t even move the array pointer (as foreach
would do).
Having the keys, one can get the values by the keys directly.
Examples (all of them require PHP 7.3+)
Getting the first/last key and value:
$my_array = ['IT', 'rules', 'the', 'world'];
$first_key = array_key_first($my_array);
$first_value = $my_array[$first_key];
$last_key = array_key_last($my_array);
$last_value = $my_array[$last_key];
Getting the first/last value as one-liners, assuming the array cannot be empty:
$first_value = $my_array[ array_key_first($my_array) ];
$last_value = $my_array[ array_key_last($my_array) ];
Getting the first/last value as one-liners, with defaults for empty arrays:
$first_value = empty($my_array) ? 'default' : $my_array[ array_key_first($my_array) ];
$last_value = empty($my_array) ? 'default' : $my_array[ array_key_last($my_array) ];
2
Shorten with null-coalescing operator, usually null is default so:
$first_value = $my_array[array_key_first($my_array)] ?? null;
From PHP 7.3, this should be the selected answer.
Some arrays don’t work with functions like list
, reset
or current
. Maybe they’re “faux” arrays – partially implementing ArrayIterator, for example.
If you want to pull the first value regardless of the array, you can short-circuit an iterator:
foreach($array_with_unknown_keys as $value) break;
Your value will then be available in $value
and the loop will break after the first iteration. This is more efficient than copying a potentially large array to a function like array_unshift(array_values($arr)).
You can grab the key this way too:
foreach($array_with_unknown_keys as $key=>$value) break;
If you’re calling this from a function, simply return early:
function grab_first($arr) {
foreach($arr as $value) return $value;
}
1
I suppose this is one of the fastest ways because using the language construct foreach rather than a function call (which is more expensive). designcise.com/web/tutorial/…
Suppose:
$array = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
Just use:
$array[key($array)]
to get first element or
key($array)
to get first key.
Or you can unlink the first if you want to remove it.
1
Wht not simply use
current
then?
From Laravel’s helpers:
function head($array)
{
return reset($array);
}
The array being passed by value to the function, the reset() affects the internal pointer of a copy of the array, and it doesn’t touch the original
array (note it returns false
if the array is empty).
Usage example:
$data = ['foo', 'bar', 'baz'];
current($data); // foo
next($data); // bar
head($data); // foo
next($data); // baz
Also, here is an alternative. It’s very marginally faster, but more interesting. It lets easily change the default value if the array is empty:
function head($array, $default = null)
{
foreach ($array as $item) {
return $item;
}
return $default;
}
For the record, here is another answer of mine, for the array’s last element.
0
Keep this simple! There are lots of correct answers here, but to minimize all the confusion, these two work and reduce a lot of overhead:
key($array)
gets the first key of an array
current($array)
gets the first value of an array
EDIT:
Regarding the comments below. The following example will output: string(13) "PHP code test"
$array = array
(
'1' => 'PHP code test',
'foo' => 'bar', 5 , 5 => 89009,
'case' => 'Random Stuff: '.rand(100,999),
'PHP Version' => phpversion(),
0 => 'ending text here'
);
var_dump(current($array));
3
Uhh.
current
equals current element. You have to reset the pointer to the beginning of the array to ensure it is actually at the beginning.current () will get the current element, not the first element. It’s different.
– amir22current will work if there is only one element in the array.
Simply do:
array_shift(array_slice($array,0,1));
1
It is an unattractive (and unexplained) technique since there are single-call techniques to achieve the same thing.
I would do echo current($array)
.
6
@hsz Doesn’t matter,
current()
doesn’t error when non-references are passed. Provided that the pointer is still at the beginning this works.– Dan Luggbut it produces a Notice which makes your logs dirty and well… you should get rid of Notices also wven if they are not critical
– dmikam@dmikam no it does not. Actually
reset
produces the “Only variables should be passed by reference” notice whilecurrent
does not: Online PHP Editor example ofcurrent(array_filter(...));
.@CPHPython, seems like you are right… looks like I had this idea of current from old times of PHP 4 where it really produces Fatal error: sandbox.onlinephpfunctions.com/code/… The only issue I see in using current is that it does not guarantee that the returned element is the first element of an array (internal pointer may be modified by the called function). Virtually it may return random element of an array.
– dmikam@CPHPython A bit artificial example, but it demonstrates well my thoughts: sandbox.onlinephpfunctions.com/code/… just imagine that you receive your array from some function that uses
next()
,end()
or any other function that modifies array’s internal pointer. In my example,current()
returns null because the internal pointer is “out of range” of array. But it may ‘virtually’ point to any/random element too.– dmikam
$arr = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
foreach($arr as $first) break;
echo $first;
Output:
apple
PHP 7.3 added two functions for getting the first and the last key of an array directly without modification of the original array and without creating any temporary objects:
“There are several ways to provide this functionality for versions prior to PHP 7.3.0. It is possible to use array_keys(), but that may be rather inefficient. It is also possible to use reset() and key(), but that may change the internal array pointer. An efficient solution, which does not change the internal array pointer, written as polyfill:”
<?php
if (!function_exists('array_key_first')) {
function array_key_first($arr) {
foreach($arr as $key => $unused) {
return $key;
}
return NULL;
}
}
if (!function_exists('array_key_last')) {
function array_key_last($arr) {
return array_key_first(array_reverse($arr, true));
}
}
?>
$myArray = array (4 => 'apple', 7 => 'orange', 13 => 'plum');
$arrayKeys = array_keys($myArray);
// The first element of your array is:
echo $myArray[$arrayKeys[0]];
1
$array=array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
$firstValue = each($array)[1];
This is much more efficient than array_values()
because the each()
function does not copy the entire array.
For more info see http://www.php.net/manual/en/function.each.php
3
because the each() function does not copy the entire array.
+1– user1646111But the thing is that you should do a reset before, if the internal pointer is not at the beginning you are not going to get the first element.
But each() receives an array by reference and the requirement of the initial questions is not to do so
– dmikam
Get first element:
array_values($arr)[0]
Get last element
array_reverse($arr)[0]
1
Numeric keys are preserved with array_reverse, so that will still return the first element. 3v4l.org/2729s
A kludgy way is:
$foo = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
function get_first ($foo) {
foreach ($foo as $k=>$v){
return $v;
}
}
print get_first($foo);
2
At least you’re honest – it’s kludgy! But, it works, and I’ve used it in the past until learning the list() technique above.
If you are doing this, you might as well use
reset()
as the array pointer is reset beforeforeach
is called anyway.– Tyzoid
Most of these work! BUT for a quick single line (low resource) call:
$array = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
echo $array[key($array)];
// key($array) -> will return the first key (which is 4 in this example)
Although this works, and decently well, please also see my additional answer:
https://stackoverflow.com/a/48410351/1804013
3
This is equivalent to using
current($array)
, which requires that the array’s internal pointer be at the first element anyway, in which case,echo reset($array)
is most appropriate.– Tyzoid@Tyzoid he actually wrote another answer here with your suggestion, but he omitted your explanation… Thank you.
Use:
$first = array_slice($array, 0, 1);
$val= $first[0];
By default, array_slice
does not preserve keys, so we can safely use zero as the index.
This is a little late to the game, but I was presented with a problem where my array contained array elements as children inside it, and thus I couldn’t just get a string representation of the first array element. By using PHP’s current()
function, I managed this:
<?php
$original = array(4 => array('one', 'two'), 7 => array('three', 'four'));
reset($original); // to reset the internal array pointer...
$first_element = current($original); // get the current element...
?>
Thanks to all the current solutions helped me get to this answer, I hope this helps someone sometime!
0
I think using array_values would be your best bet here. You could return the value at index zero from the result of that function to get ‘apple’.
Two solutions for you.
Solution 1 – Just use the key. You have not said that you can not use it. 🙂
<?php
// Get the first element of this array.
$array = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
// Gets the first element by key
$result = $array[4];
// Expected result: string apple
assert('$result === "apple" /* Expected result: string apple. */');
?>
Solution 2 – array_flip() + key()
<?php
// Get first element of this array. Expected result: string apple
$array = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
// Turn values to keys
$array = array_flip($array);
// You might thrown a reset in just to make sure
// that the array pointer is at the first element.
// Also, reset returns the first element.
// reset($myArray);
// Return the first key
$firstKey = key($array);
assert('$firstKey === "apple" /* Expected result: string apple. */');
?>
Solution 3 – array_keys()
echo $array[array_keys($array)[0]];
No one has suggested using the ArrayIterator class:
$array = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
$first_element = (new ArrayIterator($array))->current();
echo $first_element; //'apple'
gets around the by reference stipulation of the OP.
1
This should be the correct answer. Also works to get the first key:
(new ArrayIterator($array))->key()
. Note that it correctly returnsnull
for both value and key when the array is empty (rather than returning a pseudo-value likefalse
). Unfortunately doesn’t work for Laravel’s Collection class though, it always returnsnull
I imagine the author just was looking for a way to get the first element of an array after getting it from some function (mysql_fetch_row, for example) without generating a STRICT “Only variables should be passed by reference”.
If it so, almost all the ways described here will get this message… and some of them uses a lot of additional memory duplicating an array (or some part of it). An easy way to avoid it is just assigning the value inline before calling any of those functions:
$first_item_of_array = current($tmp_arr = mysql_fetch_row(...));
// or
$first_item_of_array = reset($tmp_arr = func_get_my_huge_array());
This way you don’t get the STRICT message on screen, nor in logs, and you don’t create any additional arrays. It works with both indexed AND associative arrays.
Use array_keys()
to access the keys of your associative array as a numerical indexed array, which is then again can be used as key for the array.
When the solution is arr[0]
:
(Note, that since the array with the keys is 0-based index, the 1st
element is index 0)
You can use a variable and then subtract one, to get your logic, that 1 => 'apple'
.
$i = 1;
$arr = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
echo $arr[array_keys($arr)[$i-1]];
Output:
apple
Well, for simplicity- just use:
$arr = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
echo $arr[array_keys($arr)[0]];
Output:
apple
By the first method not just the first element, but can treat an associative array like an indexed array.
I don’t like fiddling with the array’s internal pointer, but it’s also inefficient to build a second array with array_keys()
or array_values()
, so I usually define this:
function array_first(array $f) {
foreach ($f as $v) {
return $v;
}
throw new Exception('array was empty');
}
Try this:
$fruits = array( 4 => 'apple', 7 => 'orange', 13 => 'plum' );
echo reset($fruits)."n";
What do you mean, can’t be done by reference?
Function should not works using
&$array
as params.I suspect that what you “really” mean by “can’t be done by reference”, is that your array is being returned dynamically from a database, and you don’t want to pass the array into a variable before taking the first element from it. If I’m right, then the vast majority of all the solutions provided to you below (including the accepted answer), are insufficient.
Do you just have to get it or get it and remove it from the existing array?
For basic use of Arrays you can review this link technofusions.com/introduction-to-arrays-in-php