<?php
$string1 = "ABCDEFGHKPQRTVWXYZ";
$string2 = "123456789";
$string = $string1 . $string2;
$string1 = str_shuffle($string1);
$string2 = str_shuffle($string2);
$captcha_letter = substr($string1, 0, 2);
$captcha_num = substr($string2, 0, 4);
$result = $captcha_letter . $captcha_num;
echo $result ;
?>
Save log result new line
file_put_contents(‘log.txt’, json_encode( $result).PHP_EOL, FILE_APPEND);