Text file into PHP array & search for string

I've searched long and hard for an answer to doing this & have come up with nothing. I know someone here will have an answer.

First, I get the URL and grab the subsite out of the beginning:

<?php
// get page URL
    $pageURL = 'http';
    if ($_SERVER["HTTPS"] == "on") {$pageURL .= "s";}
    $pageURL .= "://";
    if ($_SERVER["SERVER_PORT"] != "80") {
        $pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
    } else {
        $pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];
    }
// get host name from URL
    $url = preg_replace('(https?://)', '', $pageURL);
    $affUrl = explode('.', $url);
    $aff = $affUrl[0];
?>

If the URL is affiliate1.domain.com, this returns affiliate1 as $aff.

Next, I have affiliates.txt each with a different name on each line:

affiliate1
affiliate2
affiliate-3 (yes, this is correct)

Then, I read that file into an array:

<?php
// read affiliates.txt and create array
    $affs = file("affiliates.txt"); 

// search for affiliate in array
    $inarray = array_search($aff, $affs); // i've tried in_array() also
    if ($inarray !== false) echo '<img src="affiliatelogos/$aff.jpg" class="aff-img" alt="$aff" />';
?>

However, even when I hardcode an affiliate name into array_search():

    $inarray = array_search('affiliate1', $affs);

It returns nothing. What am I doing wrong here?