使用str_replace而不是正则表达式更改url的更好方法

preg_replace('@url\(([^/].*)\)$@', preg_quote($location) . '$1', $content);

$location = 'somelocation'; // or however you're getting somelocation
if (strpos($location, '/') === 0) {
    $location = substr($location, 1);
}
str_replace('url(', 'url(' . $location, $content);