Regex extract sequence of a certain format from string

[djr33]

I think this is possible, but it's beyond my ability with regex.

What I want is to extract a certain pattern from a string.

So if the pattern is "any number" then I want to extract it from any string:

'this is a string123 test'
That returns '123'.


The specific pattern I am matching is a 10-digit hexadecimal code.
This means: exactly 10 characters, each of which is 0-9a-f.

I would like the function to take a string as input and return an array containing all possible matches.

Let me know if that isn't clear.

[bluewalrus]

If the numbers are always all grouped together this should work.

$string = "this is a string123 test";
$numbers = preg_replace('/.*?(\d+).*/', '$1', $string);
echo $numbers; 

Actually on rethinking this you don't even need a regex.

You can just set it as an integer and all the text will be removed.

settype($string, "integer");

[traq]

[\dABCDEF]{10}

untested.

I think [0-9A-F]{10} would work equally well, and [0-9A-Fa-f]{10} if you might have lowercase hex numbers.

[james438]

Could I have a better example of some of the text that you need processed? For example the following would work:

<?php
$css = "this is a test:ade40275ad tadaa.bde40275ad ade40275ad ade40275ad";
preg_match_all('/[a-fA-F0-9]{10}/s', $css, $match);
print_r($match);
?>

resulting in:

Array ( [0] => Array ( [0] => ade40275ad [1] => bde40275ad [2] => ade40275ad 
[3] => ade40275ad ) )

I suspect that the parameters that you are working with are somewhat more complicated than that.

[djr33]

Bluewalrus, thanks for the post, but I need this for hexadecimal not just regular integers. I like that creative method though. It actually might be possible if I set the format of the number of hexadecimal then try that... not sure if PHP is capable of ordering it that way though.

Adrian and James, thanks! One of those will work, I'm sure.
Yes, it might be lowercase or uppercase.
No, it shouldn't be much more complex than that.

I'm creating a verification system so that users must reply to an email and the subject line contains a verification sequence (a 10 digit portion of an md5-generated hash string). The email will be sent to them. All they need to do is reply. In most cases the subject line will still be "{seq}" or "RE: {seq}" but I don't want it to fail if the user does something unexpected. Additionally, if there is something wrong with the email sent to them or they want to reply from a different account, they might type it manually in a different email.

The purpose of this is to create an email based uploading system so that users on mobile devices can attach an image or audio clip to an email sent to my server [an automatically managed email address/account] that then will check incoming messages and "upload" attachments to the server. Of course I don't want just any files getting through since users must be registered, so I will give them a 'key' for each 'upload' and they just need to include that somewhere in the subject line of the email.

Very complex to figure out, but worth it because it's pretty easy for the user and in many cases mobile browsers don't have the ability to do a normal file upload. For example, the iphone. But it can attach a file to an email and send it, so that's all that needs to be done here.

[traq]

cool... I'd actually be interested in how you're checking the email and uploading the attachments from it.

[djr33]

I'm using the IMAP functions to connect to an email account.

The system isn't polished yet, but it is functional. If you want to see some specific code, contact me directly.

It's not really something I can easily post here since it exists in several pieces (and I wouldn't want to until it's worked out a bit more).

The hardest part was simply figuring out how to deal with the mail server. The rest is just step by step in PHP-- not "easy" exactly, but a lot easier than figuring out the mail server and connecting to it.

Another problem is that it either needs to run as a cron job or be triggered by the user, and either way it's not fast: about a 3 second delay to check and parse the messages (connection time, not transfer time for files-- that's fast usually, not noticable).

[traq]

hmm.

I've had a passing curiosity about emailing stuff to my website (like Facebook mobile allows). I'll look into IMAP, and drop you a note if I want to know more.

thanks

[djr33]

It's all very possible, but as I said, the biggest problem becomes the cron job part of it. It's easy to send an email because you have a triggering event (user doing something) but checking for emails ends up with the same problem that creating a chat script does: basically you need to constantly refresh. Cron jobs may be the answer, but they're not efficient for the server.
Let me know how it goes. I've been curious about this for a while too but never had a specific need to try it.

[traq]

well, I may not provide an answer. I'd probably be happy with using my login as a trigger to check for emails.

(actually, that's a hacky solution, but it would probably work pretty well - every time you serve a page to a logged-in user, check that user's "inbox." I think you could use ob_start() + ob_flush() to effectively do it in the background -serve all the page content first, then deal with the email connection... serve a little bit of ajax to wait for the response, or save it to the session and display on the next page load.)

Edit:

I may be completely wrong, however.