使用数字范围PHP搜索strpos（）

I want to search a rule, iptables, within a string that has a port blocked—and I want to show that port.

For example, the rule iptables -A OUTPUT -p tcp --dport 8080 -j DROP; I'd like to be able to search by strpos the string tcp --dport 8080 -j DROP but with a range of numbers 1-65335 instead of 8080.

Please excuse my poor English.

Assuming each string is in fixed format like your example, you can search for the number then check if within range using preg_match() function

$str = 'iptables -A OUTPUT -p tcp --dport 8080 -j DROP;';

preg_match('/\d+/', $str, $match); // search for matches
if ($match[0] >= 1 && $match[0] <= 65335) {
    echo "Valid number found on string";
}

Pattern /\d+/ searches for any digit, 1 to unlimited times

Notes:
1. Will cause undefined errors/warnings when no number found on string
2. May become inaccurate when more than 1 whole number found