PHP component that generares random string from regex

Question

I am searching for PHP component that generates random string from regex. I've searched through this forum, but found only PERL etc. solutions (Random string that matches a regexp). Is there such an open source class?

regexes are for matching strings that have already been generated, not generating them. — Jonathan Kuhn, Jan 09 '14 at 21:02
Generally questions asking for libraries etc. are off topic for SO; you might reword your question referencing the PERL solutions you found and how to convert to PHP. — brandonscript, Jan 09 '14 at 21:02
@Jonathan Kuhn: In other words I want to generate random string that will match a selected regex. — Michal, Jan 09 '14 at 21:04
possible duplicate of [Random string that matches a regexp](http://stackoverflow.com/questions/205411/random-string-that-matches-a-regexp) — KeyNone, Jan 09 '14 at 21:06
If you know the rules of the regex, in php you would probably just create a list of allowable characters and build your random string by selecting random characters from that list. — Jonathan Kuhn, Jan 09 '14 at 21:07
@Basti M ... Ok, so what is the PHP equivalent for String::Random mentioned in http://stackoverflow.com/questions/205411/random-string-that-matches-a-regexp?lq=1 ? — Michal, Jan 09 '14 at 21:08
look at [this answer](http://stackoverflow.com/a/15969145/1807643), it mentions a php lib — KeyNone, Jan 09 '14 at 21:09

brandonscript · Answer 1 · 2014-01-09T21:13:13.923

~~I'm not familiar~~ I wasn't (until now) familiar with any php libraries that can do this, and converting something like xeger would be a tremendous undertaking.

Instead, you could simply do something like this:

function random($length)
{
    $random_string = "";
    $valid_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!@#$%^&*()_+-=[]{}\\|";

    $num_valid_chars = strlen($valid_chars);

    for ($i = 0; $i < $length; $i++)
    {
        $random_pick = mt_rand(1, $num_valid_chars);
        $random_char = $valid_chars[$random_pick-1];
        $random_string .= $random_char;
    }
    return $random_string;
}

echo random(20); //generates a random string, 20 characters long.

Simplified this answer: `$validCharacters = range(0, 9); //select your char using range()` Then `$randVal = implode('', array_rand ( $validCharacters , $length ));` — Ng Sek Long, Jan 08 '21 at 05:25

score 4 · Accepted Answer · edited May 23 '17 at 11:52

A library called ReverseRegex can be found here.
As of January 2014 the project seems not to be dead.

Usage seems to be as simple as

$lexer = new  Lexer('[a-z]{10}');
$gen   = new SimpleRandom(10007);
$result = '';

$parser = new Parser($lexer,new Scope(),new Scope());
$parser->parse()->getResult()->generate($result,$gen);

echo $result;

Give it a regex, give it a random seed and generate your string.
The above example, taken from the github-site, generates a ten character long random string consisting only of letters.

(originally found in this answer)

PHP component that generares random string from regex

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