function Unicode::truncate
Same name in other branches
- 9 core/lib/Drupal/Component/Utility/Unicode.php \Drupal\Component\Utility\Unicode::truncate()
- 10 core/lib/Drupal/Component/Utility/Unicode.php \Drupal\Component\Utility\Unicode::truncate()
- 11.x core/lib/Drupal/Component/Utility/Unicode.php \Drupal\Component\Utility\Unicode::truncate()
Truncates a UTF-8-encoded string safely to a number of characters.
Parameters
string $string: The string to truncate.
int $max_length: An upper limit on the returned string length, including trailing ellipsis if $add_ellipsis is TRUE.
bool $wordsafe: If TRUE, attempt to truncate on a word boundary. Word boundaries are spaces, punctuation, and Unicode characters used as word boundaries in non-Latin languages; see Unicode::PREG_CLASS_WORD_BOUNDARY for more information. If a word boundary cannot be found that would make the length of the returned string fall within length guidelines (see parameters $max_length and $min_wordsafe_length), word boundaries are ignored.
bool $add_ellipsis: If TRUE, add '...' to the end of the truncated string (defaults to FALSE). The string length will still fall within $max_length.
int $min_wordsafe_length: If $wordsafe is TRUE, the minimum acceptable length for truncation (before adding an ellipsis, if $add_ellipsis is TRUE). Has no effect if $wordsafe is FALSE. This can be used to prevent having a very short resulting string that will not be understandable. For instance, if you are truncating the string "See myverylongurlexample.com for more information" to a word-safe return length of 20, the only available word boundary within 20 characters is after the word "See", which wouldn't leave a very informative string. If you had set $min_wordsafe_length to 10, though, the function would realise that "See" alone is too short, and would then just truncate ignoring word boundaries, giving you "See myverylongurl..." (assuming you had set $add_ellipses to TRUE).
Return value
string The truncated string.
28 calls to Unicode::truncate()
- BookManager::recurseTableOfContents in core/
modules/ book/ src/ BookManager.php - Recursively processes and formats book links for getTableOfContents().
- CommentAdminOverview::buildForm in core/
modules/ comment/ src/ Form/ CommentAdminOverview.php - Form constructor for the comment overview administration form.
- CommentAdminTest::testApprovalAdminInterface in core/
modules/ comment/ tests/ src/ Functional/ Views/ CommentAdminTest.php - Test comment approval functionality through admin/content/comment.
- CommentForm::buildEntity in core/
modules/ comment/ src/ CommentForm.php - Builds an updated entity object based upon the submitted form values.
- CommentPermalinkFormatter::getEntityUrl in core/
modules/ comment/ src/ Plugin/ Field/ FieldFormatter/ CommentPermalinkFormatter.php - Gets the URI elements of the entity.
File
-
core/
lib/ Drupal/ Component/ Utility/ Unicode.php, line 420
Class
- Unicode
- Provides Unicode-related conversions and operations.
Namespace
Drupal\Component\UtilityCode
public static function truncate($string, $max_length, $wordsafe = FALSE, $add_ellipsis = FALSE, $min_wordsafe_length = 1) {
$ellipsis = '';
$max_length = max($max_length, 0);
$min_wordsafe_length = max($min_wordsafe_length, 0);
if (mb_strlen($string) <= $max_length) {
// No truncation needed, so don't add ellipsis, just return.
return $string;
}
if ($add_ellipsis) {
// Truncate ellipsis in case $max_length is small.
$ellipsis = mb_substr('…', 0, $max_length);
$max_length -= mb_strlen($ellipsis);
$max_length = max($max_length, 0);
}
if ($max_length <= $min_wordsafe_length) {
// Do not attempt word-safe if lengths are bad.
$wordsafe = FALSE;
}
if ($wordsafe) {
$matches = [];
// Find the last word boundary, if there is one within $min_wordsafe_length
// to $max_length characters. preg_match() is always greedy, so it will
// find the longest string possible.
$found = preg_match('/^(.{' . $min_wordsafe_length . ',' . $max_length . '})[' . Unicode::PREG_CLASS_WORD_BOUNDARY . ']/us', $string, $matches);
if ($found) {
$string = $matches[1];
}
else {
$string = mb_substr($string, 0, $max_length);
}
}
else {
$string = mb_substr($string, 0, $max_length);
}
if ($add_ellipsis) {
// If we're adding an ellipsis, remove any trailing periods.
$string = rtrim($string, '.');
$string .= $ellipsis;
}
return $string;
}
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