使用mb_substr仍然会在最后破坏重音字符

Question

Logic: I am getting username from DB and if it is greater than 30 in length then i show 30 characters with "..." appended at the end. Code is

$username = htmlspecialchars($username);
if(mb_strlen($username, 'utf-8')>30){
    $username_trimmed = mb_substr($username, 0, 30, 'utf-8').'...';
}

and in my navivation I am just printing this username

<class="userName">Hello, <?php echo $username_trimmed; ?>

My encoding in set as utf-8, and mbstring extension is enabled in php.

Output of above code : It still breaks the accent character É because it is multi-byte character and it is getting cut the in the middle. Actual word is MARCHÉS and output is:

Question what am I missing? mb_substr should not consider it as a single character and should not stop it from breaking in the middle as it does?

Answer 1

Your string is actually "É", not "É". mb_substr handles your characters just fine, it does not handle HTML entities. Don't store HTML entities in your database, store actual Unicode characters. At the very least, decode from HTML entities to actual characters using html_entity_decode($str, ENT_COMPAT, 'UTF-8') before applying mb_substr (and then apply htmlspecialchars again afterwards to preserve HTML syntax).