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  1. <?php
  2.  
  3. if (!preg_match('~^[A-Z0-9]*(?:\.[A-Z0-9]*)?$~i', 'abc.def.ghi'))
  4. {
  5.     echo "Invalid Username";
  6. }
Success #stdin #stdout 0.01s 23808KB
comments (?)
stdin 
Standard input is empty
stdout 
Invalid Username
https://ideone.com/vmjg9J
language:
PHP (php 7.3.5)
created:
6 years ago
visibility:
secret

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