- var_dump: documentation ( source)
- bin2hex: documentation ( source)
- mb_check_encoding: documentation ( source)
<?php
$invalid_utf8="\xF5\x80\x80\x80PHP";
$should_be_valid_utf8=iconv("UTF-8","UTF-8//IGNORE",$invalid_utf8);
var_dump($should_be_valid_utf8,bin2hex($should_be_valid_utf8),mb_check_encoding($should_be_valid_utf8));