PHP（RegEx）IP地址验证

Posted 2021-02-27

A simple method of validating an IP address using php and regular expressions

$string = "255.255.255.255";
if (preg_match(
'/^(?:25[0-5]|2[0-4]d|1dd|[1-9]d|d)(?:[.](?:25[0-5]|2[0-4]d|1dd|[1-9]d|d)){3}$/',
$string)) { 
echo "IP address is good.";
}