Detect Chrome and Firefox

detectbrowser.php

<?php
    // Please note that User Agents can be *EASILY* spoofed. Don't use this as a
    // reliable indicator for security purposes. ie. don't trust anything the user
    // tells you - that includes user agents and IP addresses.
    
    function detectBrowser($useragent) {
        $detectedBrowser = explode(" ", $useragent, 20);
        $temp["dtbr_counter"] = true; foreach ($detectedBrowser as &$value) {
            if ($temp["dtbr_counter"]) {
                $temp["dtbr_exploded"] = explode("/", $value);
                if ($temp["dtbr_exploded"][0] === "Chrome" || $temp["dtbr_exploded"][0] === "Firefox") {
                    unset($detectedBrowser); $detectedBrowser["browser"] = $temp["dtbr_exploded"][0];
                    $detectedBrowser["version"] = $temp["dtbr_exploded"][1]; 
                    $detectedBrowser["browser_string"] = $detectedBrowser["browser"]." ".$detectedBrowser["version"];
                    $temp["dtbr_counter"] = false; return $detectedBrowser;
                }
            }
        }
    }

    echo detectBrowser($_SERVER['HTTP_USER_AGENT'])["browser_string"];
?>