匹配网址中的特定正则表达式单词

Question

I must admit I've never gotten used to using regex, however recently I ran into a problem where the work around would've been more of a pain than using regex. I need to be able to match anything that follows the following pattern at the beginning of a string: {any_url_safe_word} +( "/http://" || "/https://" || "www." ) + {any word} . So the following should match:

• cars/http://google.com#test
• cars/https://google.com#test
• cars/www.google.com#test

The follwing shouldn't match:

• cars/httdp://google.com#test
• cars/http:/google.com#test

What I tried so far is: ^[\\w]{1,500}\\/[(http\\:\\/\\/)|(https:\\/\\/])|([www\\.])]{0,50} , but that matches cars/http from cars/httpd://google.com .

Answer 1

This regex could do:

^[\w\d]+\/(?:https?:\/\/)?(?:www\.)?[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}

And if you want to get everything that comes after it, you can just add (.*) to the end...

Live DEMO

And since it seems that the more or less general list of URL safe words contains ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;= Source , you may include that too, so you'll get (after simplification):

^[!#$&-.0-;=?-\[\]_a-z~]+\/(?:https?:\/\/)?(?:www\.)?[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}

Answer 2

<?php
$words = array(
    'cars/http://google.com#test',
    'cars/https://google.com#test',
    'cars/www.google.com#test',
    'cars/httdp://google.com#test',
    'cars/http:/google.com#test',
    'c a r s/http:/google.com#test'
    );

foreach($words as $value)
{
    /*
      \S+           - at least one non-space symbol
      \/            - slash
      (https?:\/\/) - http with possible s then ://
      |             - or
      (www\.)       - www.
      .+            - at least one symbol
     */
    if (preg_match('/^\S+\/(https?:\/\/)|(www\.).+/', $value))
    {
        print $value. " good\n";
    }
    else
    {
        print $value. " bad\n";
    }
}

Prints:

cars/http://google.com#test good
cars/https://google.com#test good
cars/www.google.com#test good
cars/httdp://google.com#test bad
cars/http:/google.com#test bad
c a r s/http:/google.com#test bad

Answer 3

Check out the demo .

[a-z0-9-_.~]+/(https?://|www\\.)[a-z0-9]+\\.[az]{2,6}([/?#a-z0-9-_.~])*

Edit: taken @CD001 comment into account. Be sure to use the i modifier if you don't mind case-sensitivity.