Using ereg_replace or preg_replace to leave part of a filename in php

Question

I am trying to leave only the prefix (WST in the example below) and the number. Any suffix and file extension should be removed. This should leave me with the product code in tact.

Here are three possible values:

39159 FLAN.jpg
22201-HAV.jpg
WST 503.jpg

The output I need for these three examples is:

39159
22201
WST 503

Here is my current ereg_replace, but it also removes the prefix before the number:

$number  = ereg_replace("[^0-9]", "", $value);

Stop using `ereg_replace()`. It's obsolete! – bcosca Dec 07 '10 at 11:13 — bcosca, Dec 07 '10 at 11:13

rik · Answer 1 · 2010-12-07T11:25:45.327

0

The ereg* functions are deprecated. You should not use them anymore.

$name = basename($value, '.jpg');

Now you have the filename without extension in $name. You can split the name and number into separate variables like this:

$name = str_replace('-', ' ', $name);
if (is_numeric($name[0])) {
    list($number, $garbage) = explode(' ', $name);
    $prefix = null; unset($garbage);
} 
else list($prefix, $number) = explode(' ', $name);

This code only works correctly if the prefix never starts with a number though. But you get the idea.

edited Dec 07 '10 at 11:25

answered Dec 07 '10 at 11:18

rik

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This will leave "FLAN", "HAV" e.t.c in my examples? I need that removed also! So its just prefix+number – Andy Dec 07 '10 at 11:21
I'm sorry, thought "FLAN" and "HAV" should be extracted as prefixes as well, even if they are not real "pre"-fixes. I changed my code. Now you only get the "real" prefixes. – rik Dec 07 '10 at 11:25
Thanks Rik, no doubt this would have worked as well but i've opted for Kobi's solution as it was simpler. Thanks again! – Andy Dec 07 '10 at 11:31

score 0 · Accepted Answer · answered Dec 07 '10 at 11:22

One option is to remove anything after the last digit. This may not work as expected if you have more than one number in the name:

preg_replace("/\D+$/", "WST 503.jpg", "");

Another, probably stronger option is to capture the first number, and anything before it:

preg_match("/^\D*\d+/", "WST 503.jpg", $matches);
print_r($matches);  // [0] => WST 503

score 0 · Answer 3 · answered Dec 07 '10 at 11:26

<?php
function showProductNumberFromFilename($filename) {
  // split filename
  $filenameParts = explode('.', $filename);

  // get extension
  $extension = end($filenameParts);

  // remove extension
  $productNumber = str_replace($extension, '', $filename);

  return substr($productNumber, 0, -1);
}

// echos 3159 FLAN
echo showProductNumberFromFilename('39159 FLAN.jpg');

// echos 22201-HAV
echo showProductNumberFromFilename('22201-HAV.jpg');

// echos WST 503
echo showProductNumberFromFilename('WST 503.jpg');
?>

quick and dirty script ;-)

Using ereg_replace or preg_replace to leave part of a filename in php

3 Answers3