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<?php $name = "He/llo W+or_ld Test=Code"; if( preg_match_all('/[^a-zA-Z ]/', $name, $res) ){ echo "Unavailable Characters: " . implode('', $res[0]); }
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
Unavailable Characters: /+_=
preferences:
130.1 ms | 407 KiB | 5 Q