Regex to delete words with numbers - php

Question

I would like to delete words with numbers (reference) or small words (2 characters or less) into my product name but I can't find the good regex.
Some examples:
"Chaine anti-rebond ECS-2035" should become "Chaine anti-rebond"
"Guide 35 cm Oregon Intenz" should become "Guide Oregon Intenz"
"Tronçonneuse sans fil AKE 30 LI - Guide 30 cm 36 V" should become "Tronçonneuse sans fil AKE - Guide"
I'm doing this in PHP:
preg_replace('#([^A-Za-z-]+)#', ' ',' '.wd_remove_accents($modele).' ');

Answer 1

You don't need to do everything in RegExp you know:
<?php
$str = "Chaine anti-rebond ECS-2035 cm 30 v";
$result = array();
$split = explode(" ", $str); //Split to an array
foreach ($split as $word) {
if ((strlen($word) <= 2) || (preg_match("|\d|", $word))) { //If word is <= 2 char long, or contains a digit
continue; //Continue to next iteration immediately
}
$result[] = $word; //Add word to result array (would only happen if the above condition was false)
}
$result = implode(" ", $result); //Implode result back to string
echo $result;
For word based string manipulation, parsing the string itself, conditioning exactly what you want on a word basis, is often much better than a string-level RegExp.

Answer 2

To deal with unicode characters like in tronçonneuse you could use:
/\b(?:[\pL-]+\pN+|\pN+[\pL-]+|\pN+|\pL{1,2})\b/
where \pL stands for any letter and \pN stands for any digit.

Answer 3

Your requirements aren't specific enough for a final answer, but this would do it for your example:
$subject = 'Tronçonneuse sans fil AKE 30 LI - Guide 30 cm 36 V';
$regex = '/(\\s+\\w{1,2}(?=\\W+))|(\\s+[a-zA-Z0-9_-]+\\d+)/';
$result = preg_replace($regex, '', $subject);

Answer 4

Well, for the combinations in your example the following regex would do:
/\b(?:[-A-Za-z]+[0-9]+|[0-9]+[-A-Za-z]+|\d{1,2}|[A-Za-z]{1,2})\b/
Then just replace the match with an empty string.
However, it doesn't allow for strings like aaa897bbb - just aaa786 or 876aaa (and an optional dash).
I don't know what it is that you require - you would have to specify the rules in more detail before the regex can be refined.

Answer 5

Use preg_replace_callback and filter in the callback function http://www.php.net/manual/en/function.preg-replace-callback.php
This will work for all 3 test strings:
<?php
$str = "Tronçonneuse sans fil AKE 30 LI - Guide 30 cm 36 V";
function filter_cb($matches)
{
$word = trim($matches[0]);
if ($word !== '-' && (strlen($word) <= 2 || (preg_match("/\d/", $word)))) {
return '';
}
return $matches[0];
}
$result = preg_replace_callback('/([\p{L}\p{N}-]+\s*)/u', "filter_cb", $str);
echo trim($result);