Matching a Valid IP Address : Regular Expressions « String « PHP






  1. PHP
  2. String
  3. Regular Expressions

Matching a Valid IP Address

 
<?php 

$good_ip = "192.168.0.1"; 

$bad_ip = "1.334.10.10"; 

$regex = "^(([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){3}.([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$" ;

if (ereg($regex, $good_ip)) { 
    echo "'" . $good_ip . "' is a valid ip address.\n"; 
} else { 
    echo "'" . $good_ip . "' is an INVALID ip address.\n"; 
} 

if (ereg($regex, $bad_ip)) { 
    echo "'" . $bad_ip . "' is a valid ip address.\n"; 
} else {
    echo "'" . $bad_ip . "' is a INVALID ip address.\n"; 
} 
?>








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