how to remove anything without numbers and extension with regex? - php

Question

i have file like this 1248812832.v.doc and i want to remove strings and dots frome database fields to make the file like this 1248812832.doc
i use this code but it not work perfectly i still see strings and dots
<?php
$host = 'localhost';
$username = 'root';
$password = '';
$database = 'alsidik';
$conn = mysql_connect($host, $username, $password);
if (!$conn) {
echo "Unable to connect to DB: " . mysql_error();
exit;
}
if (!mysql_select_db($database)) {
echo "Unable to select " . $database . ": " . mysql_error();
exit;
}
$sql = "SELECT * FROM d_jobs";
$result = mysql_query($sql);
if (!$result) {
echo "Could not successfully run query ($sql) from DB: " . mysql_error();
exit;
}
if (mysql_num_rows($result) == 0) {
echo "No rows found, nothing to print so am exiting";
exit;
}
while ($row = mysql_fetch_assoc($result)) {
$id = $row['jb_id'];
$jb_cv = $row['jb_cv'];
$jb_rep = preg_replace('/[^.a-z0-9.]/','', $jb_cv);
$sql = "UPDATE d_jobs set jb_cv='" .$jb_rep. "' where jb_id=" . $id;
mysql_query($sql);
}
mysql_close($conn);
?>
can anyone help me..thanks

Answer 1

You didn't say how would you want to process this string:
$str = '1212.v.a.doc';
... so I assume you need only the first and the last parts of this string (where parts are delimited by '.' symbols). With this, you can use either...
$parts = explode('.', $str);
if (count($parts) > 2) {
$str = "$parts[0].{$parts[count($parts)-1]}";
}
... or
$str = preg_replace('#(?<=[.])([^.]*[.])+#', '', $str);
The reason for this line to fail:
preg_replace('/[^.a-z0-9.]/','', $jb_cv);
... is that you use a negative character class here (defined by [^...] part). In other words, you erase all symbols but dots, lowercase latin letters and digits from your string. That's definitely not what's wanted, I suppose; in fact, it won't alter the original string in your example at all.
UPDATE: Looks like all that jugglery was in vain, and what you actually needed is just digits and extension. Well, it can be done with regex too:
$str = '1212.v.a.doc';
$str = preg_replace('#^(\d+).*([.][^.]+)$#', '$1$2', $str);
echo $str;
... but in fact I'd prefer the #jeroen's solution for readability alone. )

Answer 2

An alternative to the explode solution: Just cast it to int and put the extension back on:
$str = '1248812832abc.v.doc';
$name = (int) $str . '.' .pathinfo($str, PATHINFO_EXTENSION);
var_dump($name);
Example on codepad.