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<?php $nik=1234567891234567; var_dump($nik); if(preg_match('/^[1-9]\d{15}$/', $nik)){ echo "Contains only numbers"; exit; }else{ echo "Contains non-numeric characters"; exit; }
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
int(1234567891234567) Contains only numbers

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129.38 ms | 408 KiB | 5 Q