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How to get the first item from an associative PHP array?

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How do you get the first key of an associative array?

Starting from PHP 7.3, there is a new built in function called array_key_first() which will retrieve the first key from the given array without resetting the internal pointer. Check out the documentation for more info. You can use reset and key : reset($array); $first_key = key($array);

How can we get the first element of an array in PHP?

There are several methods to get the first element of an array in PHP. Some of the methods are using foreach loop, reset function, array_slice function, array_values, array_reverse, and many more.

How can we access a specific value in an associative array in PHP?

You can use the PHP array_values() function to get all the values of an associative array.


reset() gives you the first value of the array if you have an element inside the array:

$value = reset($array);

It also gives you FALSE in case the array is empty.


PHP < 7.3

If you don't know enough about the array (you're not sure whether the first key is foo or bar) then the array might well also be, maybe, empty.

So it would be best to check, especially if there is the chance that the returned value might be the boolean FALSE:

$value = empty($arr) ? $default : reset($arr);

The above code uses reset and so has side effects (it resets the internal pointer of the array), so you might prefer using array_slice to quickly access a copy of the first element of the array:

$value = $default;
foreach(array_slice($arr, 0, 1) as $value);

Assuming you want to get both the key and the value separately, you need to add the fourth parameter to array_slice:

foreach(array_slice($arr, 0, 1, true) as $key => $value);

To get the first item as a pair (key => value):

$item = array_slice($arr, 0, 1, true);

Simple modification to get the last item, key and value separately:

foreach(array_slice($arr, -1, 1, true) as $key => $value);

performance

If the array is not really big, you don't actually need array_slice and can rather get a copy of the whole keys array, then get the first item:

$key = count($arr) ? array_keys($arr)[0] : null;

If you have a very big array, though, the call to array_keys will require significant time and memory more than array_slice (both functions walk the array, but the latter terminates as soon as it has gathered the required number of items - which is one).

A notable exception is when you have the first key which points to a very large and convoluted object. In that case array_slice will duplicate that first large object, while array_keys will only grab the keys.

PHP 7.3+

PHP 7.3 onwards implements array_key_first() as well as array_key_last(). These are explicitly provided to access first and last keys efficiently without resetting the array's internal state as a side effect.

So since PHP 7.3 the first value of $array may be accessed with

$array[array_key_first($array)];

You still had better check that the array is not empty though, or you will get an error:

$firstKey = array_key_first($array);
if (null === $firstKey) {
    $value = "Array is empty"; // An error should be handled here
} else {
    $value = $array[$firstKey];
}

Fake loop that breaks on the first iteration:

$key = $value = NULL;
foreach ($array as $key => $value) {
    break;
}

echo "$key = $value\n";

Or use each() (warning: deprecated as of PHP 7.2.0):

reset($array);
list($key, $value) = each($array);

echo "$key = $value\n";

There's a few options. array_shift() will return the first element, but it will also remove the first element from the array.

$first = array_shift($array);

current() will return the value of the array that its internal memory pointer is pointing to, which is the first element by default.

$first = current($array);

If you want to make sure that it is pointing to the first element, you can always use reset().

reset($array);
$first = current($array);

another easy and simple way to do it use array_values

array_values($array)[0]