Input data:

ip => 123.1.1.3

There is a list of .txt:

 123.123.33.3 127.0.0.1 ...

You need a function that returns true if the list contains the IP of their input data or returns false if the IP is not in the list.

2 answers 2

The first way.

If the list is small, you can use the file function to read the file and put it into an array, and then use array_search to search the array for a value. array_search searches for the given value in the array and returns the corresponding key in case of success.

IPs.txt file

 123.123.33.3 127.0.0.1

Search

 $ipToSearch = '123.1.1.3'; $ipList = file('IPs.txt'); echo array_search($ipToSearch, $ipList) ? 'YO!' : 'NO :-(';

The second way: use the loop (and the function as a wrapper, so as not to stick out the code :-))

 function findIP($ipToSearch, $file) { $fp = fopen($file, 'r'); while (!feof($fp)) { $line = trim(fgets($fp)); if ($ipToSearch == $line) return true; } fclose($fp); return false; } echo findIP('123.1.1.3', 'IPs.txt') ? 'YO!' : 'NO :-(';

fopen - Opens file or URL

fclose - closes accordingly

fgets - Reads a line from a file

ps Also you should not forget error handling for the presence of a file, for an unsuccessful attempt to read, during reading, etc.

     <?php $ip = "123.1.1.3"; $file = file_get_contents("ip.txt"); $array = explode(" ", $file); if (in_array($ip, $array)) return true; // есть в файле else return false; // нету