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<?php $names = array('Mike Cannon-Brookes', "Bill O'Hara-Jones", "Jane O'-Reilly", "Mary Smythe-'Fawkes"); foreach ($names as $name) { $name_valid = preg_match("/^(?!.*['-]{2})[a-zA-Z][a-zA-Z'\s-]{1,20}$/", $name); echo "$name is " . (($name_valid) ? "valid" : "not valid") . "\n"; }
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Mike Cannon-Brookes is valid Bill O'Hara-Jones is valid Jane O'-Reilly is not valid Mary Smythe-'Fawkes is not valid
preferences:
98.8 ms | 1695 KiB | 4 Q