PHP validation/regex for URL

Question

I\'ve been looking for a simple regex for URLs, does anybody have one handy that works well? I didn\'t find one with the zend framework validation classes and have seen sev

Answer 1

OK, so this is a little bit more complex then a simple regex, but it allows for different types of urls.

Examples:

• google.com
• www.microsoft.com/
• http://www.yahoo.com/
• https://www.bandcamp.com/artist/#!someone-special!

All which should be marked as valid.

function is_valid_url($url) {
    // First check: is the url just a domain name? (allow a slash at the end)
    $_domain_regex = "|^[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)*(\.[A-Za-z]{2,})/?$|";
    if (preg_match($_domain_regex, $url)) {
        return true;
    }

    // Second: Check if it's a url with a scheme and all
    $_regex = '#^([a-z][\w-]+:(?:/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))$#';
    if (preg_match($_regex, $url, $matches)) {
        // pull out the domain name, and make sure that the domain is valid.
        $_parts = parse_url($url);
        if (!in_array($_parts['scheme'], array( 'http', 'https' )))
            return false;

        // Check the domain using the regex, stops domains like "-example.com" passing through
        if (!preg_match($_domain_regex, $_parts['host']))
            return false;

        // This domain looks pretty valid. Only way to check it now is to download it!
        return true;
    }

    return false;
}

Note that there is a in_array check for the protocols that you want to allow (currently only http and https are in that list).

var_dump(is_valid_url('google.com'));         // true
var_dump(is_valid_url('google.com/'));        // true
var_dump(is_valid_url('http://google.com'));  // true
var_dump(is_valid_url('http://google.com/')); // true
var_dump(is_valid_url('https://google.com')); // true