How can I remove all empty values when I explode a string using PHP?

When exploding a string in PHP, you often need to remove empty values from the resulting array. There are three main approaches: using array_filter(), using array_filter() with strlen, or using preg_split() with the PREG_SPLIT_NO_EMPTY flag.

Using array_filter()

The simplest approach uses array_filter() to remove falsy values, but this also removes "0" since it evaluates to false −

<?php
$string = ",abc,defg,,,hijk,lmnop,,0,,";
echo "Original string: " . $string . "<br><br>";

echo "--- Using array_filter() ---<br>";
$result = array_filter(explode(",", $string));
var_dump($result);
?>

Original string: ,abc,defg,,,hijk,lmnop,,0,,

--- Using array_filter() ---
array(4) {
  [1]=>
  string(3) "abc"
  [2]=>
  string(4) "defg"
  [5]=>
  string(4) "hijk"
  [6]=>
  string(5) "lmnop"
}

Using array_filter() with strlen

To preserve "0" values while removing empty strings, use strlen as the callback function −

<?php
$string = ",abc,defg,,,hijk,lmnop,,0,,";

echo "--- Using array_filter() with strlen ---<br>";
$result = array_filter(explode(",", $string), 'strlen');
var_dump($result);
?>

--- Using array_filter() with strlen ---
array(5) {
  [1]=>
  string(3) "abc"
  [2]=>
  string(4) "defg"
  [5]=>
  string(4) "hijk"
  [6]=>
  string(5) "lmnop"
  [8]=>
  string(1) "0"
}

Using preg_split() with PREG_SPLIT_NO_EMPTY

The preg_split() function with PREG_SPLIT_NO_EMPTY flag removes empty values during splitting and reindexes the array −

<?php
$string = ",abc,defg,,,hijk,lmnop,,0,,";

echo "--- Using preg_split() with PREG_SPLIT_NO_EMPTY ---<br>";
$result = preg_split('/,/', $string, -1, PREG_SPLIT_NO_EMPTY);
var_dump($result);
?>

--- Using preg_split() with PREG_SPLIT_NO_EMPTY ---
array(5) {
  [0]=>
  string(3) "abc"
  [1]=>
  string(4) "defg"
  [2]=>
  string(4) "hijk"
  [3]=>
  string(5) "lmnop"
  [4]=>
  string(1) "0"
}

Comparison

Conclusion

Use array_filter() with strlen to preserve "0" values while keeping original indices. Use preg_split() with PREG_SPLIT_NO_EMPTY when you need a reindexed array without empty values.