Ignoring capital letters when reading from file in PHP

Question

I am working on a program that reads a text file, looks for a word and then depending on whether the word is found displays different outcome.

Is there a way to ignore the capital letters? So for example when I am looking for a word respond it will grab Respond, respond, RESPOND, ReSpOnd etc.

Code is:

<?php
//1 email;
$file = "1.txt";
$fh = fopen($file, 'r');
$theData = fread($fh, filesize($file));
fclose($fh);

echo "<strong>Email 1 - correct outcome: reply needed <br /></strong>"; 

if (preg_match("/dota(.*?)dota1/s", $theData, $matches))
{
    echo $matches[1]."<br />";
}

$respond   = 'Respond';

$pos = strpos($matches[1], $respond);

if ($pos === false) {
    echo "Reply not needed";
} else {
    echo "Reply needed";

}

echo "<HR>"; 
?>  

Thanks!

Answer 1

$pos = strpos($matches[1], $respond);

should be:

$pos = stripos($matches[1], $respond);

strpos() is case-sensitive, while stripos() is case-insensitive.