How to determine the first and last iteration in a foreach loop?

php loops foreach
mehdi picture mehdi · Jul 1, 2009 · Viewed 571.8k times · Source

The question is simple. I have a foreach loop in my code:

foreach($array as $element) {
    //code
}

In this loop, I want to react differently when we are in first or last iteration.

How to do this?

Answer

Rok Kralj picture Rok Kralj · Jan 8, 2012

If you prefer a solution that does not require the initialization of the counter outside the loop, I propose comparing the current iteration key against the function that tells you the last / first key of the array.

This becomes somewhat more efficient (and more readable) with the upcoming PHP 7.3.

Solution for PHP 7.3 and up:

foreach($array as $key => $element) {
    if ($key === array_key_first($array))
        echo 'FIRST ELEMENT!';

    if ($key === array_key_last($array))
        echo 'LAST ELEMENT!';
}

Solution for all PHP versions:

foreach($array as $key => $element) {
    reset($array);
    if ($key === key($array))
        echo 'FIRST ELEMENT!';

    end($array);
    if ($key === key($array))
        echo 'LAST ELEMENT!';
}

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