PHP Timer

Timer.php

<?php

class Timer {

    public static $time = array();

    public static $last;

    public static function start($name = NULL) {
        static $i = 0;
        if ($name === NULL) {
            $name = $i++;
        }
        self::$last = $name;
        self::$time[$name] = microtime(TRUE);
    }

    public static function stop($name = NULL) {
        if ($name === NULL) {
            $name = self::$last;
        }
        self::$time[$name] = (microtime(TRUE) - self::$time[$name]) * 1000;
    }

    public static function table() {
        if (!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest')
            return;
        Timer::stop('page');
        echo '<div style="position: fixed; bottom: 30%; right: 15%; z-index: 999; background-color: lightgray; padding: 15px; font-size: 13px;">';
        echo '<table>';
        foreach (self::$time as $key => $value) {
            echo '<tr><td style="padding: 2px 5px">' . $key . '</td><td>' . round($value) . ' ms</td></tr>';
        }
        echo '</table>';
        echo '</div>';
    }

}

Timer::start('page');

register_shutdown_function(array('Timer', 'table'));

function start($name) {
    Timer::start($name);
}
function stop($name = NULL) {
    Timer::stop($name);
}

function flip($name = NULL) {
    Timer::stop();
    Timer::start($name);
}