Find the last element of an array while using a foreach loop in PHP

Question

It sounds like you want something like this:

$numItems = count($arr);
$i = 0;
foreach($arr as $key=>$value) {
  if(++$i === $numItems) {
    echo "last index!";
  }
}    

That being said, you don't -have- to iterate over an "array" using foreach in php.

You could get the value of the last key of the array using end(array_keys($array)) and compare it to the current key:

$last_key = end(array_keys($array));
foreach ($array as $key => $value) {
    if ($key == $last_key) {
        // last element
    } else {
        // not last element
    }
}

Note: This doesn't work because calling next() advances the array pointer, so you're skipping every other element in the loop

---

why so complicated?

foreach($input as $key => $value) {
    $ret .= "$value";
    if (next($input)==true) $ret .= ",";
}

This will add a , behind every value except the last one!

When toEnd reaches 0 it means it is at the last iteration of the loop.

$toEnd = count($arr);
foreach($arr as $key=>$value) {
  if (0 === --$toEnd) {
    echo "last index! $value";
  }
}

The last value is still available after the loop, so if you just want to use it for more stuff after the loop this is better:

foreach($arr as $key=>$value) {
  //something
}
echo "last index! $key => $value";

If you do not want to treat the last value as special inside loops. This should be faster if you have large arrays. (If you reuse the array after the loop inside the same scope you have to "copy" the array first).

//If you use this in a large global code without namespaces or functions then you can copy the array like this:
//$array = $originalArrayName; //uncomment to copy an array you may use after this loop

//end($array); $lastKey = key($array); //uncomment if you use the keys
$lastValue = array_pop($array);

//do something special with the last value here before you process all the others?
echo "Last is $lastValue", "\n";

foreach ($array as $key => $value) {
    //do something with all values before the last value
    echo "All except last value: $value", "\n";
}

//do something special with the last value here after you process all the others?
echo "Last is $lastValue", "\n";

And to answer your original question "in my case to append or/and parameter while building query"; this will loop over all the values, then join them together to a string with " and " between them but not before the first value or after the last value:

$params = [];
foreach ($array as $value) {
    $params[] = doSomething($value);
}
$parameters = implode(" and ", $params);

There are already many answers, but it's worth to look into iterators as well, especially as it has been asked for a standard way:

$arr = range(1, 3);

$it = new CachingIterator(new ArrayIterator($arr));
foreach($it as $key => $value)
{
  if (!$it->hasNext()) echo 'Last:';
  echo $value, "\n";
}

You might find something that does work more flexible for other cases, too.