check if a string is a URL [duplicate]

Answer 1

You could use the following regex pattern to check if your variable is an url or not :

$pattern = "\b(([\w-]+:\/\/?|www[.])[^\s()<>]+(?:\([\w\d]+\)|([^[:punct:]\s]|\/)))";

Answer 2

I don't think there is a definitive answer to this. Example of a valid URL:

localhost
http://xxx.xxx.xxx/alkjnsdf
abs.com

If you have some text. and not a large amount of it. You can check by doing a CURL request and see if that returns a valid response. Otherwise if I put localhost, it could be a link and it could be something else and you wouldn't be able check it.

Answer 3

Check if it is a valid url (example.com IS NOT a valid URL)

    function isValidURL($url)
    {
        return preg_match('|^http(s)?://[a-z0-9-]+(.[a-z0-9-]+)*
        (:[0-9]+)?(/.*)?$|i', $url);
    }

How to use the function:

    if(!isValidURL($fldbanner_url))
    {
        $errMsg .= "* Please enter valid URL including http://<br>";
    }

Source: http://phpcentral.com/208-url-validation-in-php.html

Answer 4

Regexes are a poor way to validate something as complex as a URL.

PHP's filter_var() function offers a much more robust way to validate URLs. Plus, it's faster, since it's native code.

Answer 5

The code below worked for me:

if(filter_var($text, FILTER_VALIDATE_URL))
{
    echo "Yes it is url";
    exit; // die well
}
else
{
    echo "No it is not url";
   // my else codes goes
}

You can also specify RFC compliance and other requirements on the URL using flags. See PHP Validate Filters for more details.

Answer 6

PHP's filter_var function is what you need. Look for FILTER_VALIDATE_URL. You can also set flags to fine-tune your implementation.
No regex needed....