表观PHP语法错误

Basically, I've been trying to make a simple Wordpress widget that displays a QR code with the URL of the current page. I'm using a modififed version of the simple text widget that parses PHP too.

function the_qrcode($permalink = '', $title = '') {
    if($permalink && $title == '') {
        $permalink = 'http://eternityofgamers.com/forums';
        $title = 'Forums';
    }

    echo '<img src="http://api.qrserver.com/v1/create-qr-code/?data=' .$permalink. '" alt="QR: ' .$title. '"/>;
}

Can someone tell me what's wrong with this? I get a 500 error when I add it to functions.php.

Look at StackOverflow's syntax highlighting. You're missing a closing single quote ' on your string at the end of the function's last line:

echo '<img ...' .$title. '"/>;
                             ^

Close the last single quote on the echo line to be:

echo '<img src="http://api.qrserver.com/v1/create-qr-code/?data=' .$permalink. '" alt="QR: ' .$title. '"/>';