[SOLVED] regex to match image extentions suddenly not working....

[dadamssg]

I wrote an upload script and now my regex to check the extension(.jpg .gif .png) isn't working. This is the part thats throwing my error and telling me i don't have a valid file

if(!preg_match('/[.](jpg)|(gif)|(png)$/', $_FILES['fupload']['name']))  {
$_SESSION['mess'] = "Images must be JPG, GIF, or PNG.";
  extract($_POST);
   header("location: picupload.php?id={$_GET['id']}");
   exit();
}

 

help?

[Adam]

Would need to be:

 

/\.(jpg|gif|png)$/

[dadamssg]

just tried that, not workin...this seems to work though

 

if(!preg_match('/[.](jpg)|(gif)|(png)|(jpeg)|(GIF)|(PNG)|(JPG)|(JPEG)$/', $_FILES['fupload']['name']))  {
$_SESSION['mess'] = "Images must be JPG, GIF, or PNG.";
  extract($_POST);
   header("location: picupload.php?id={$_GET['id']}");
   exit();
}

[Adam]

Works here...

 

<?php

$file = 'my_image.jpg';

if (!preg_match('/\.(jpg|gif|png)$/', $file))
{
    echo 'Invalid!';
}
else
{
    echo 'Valid!';
}

?>

[nrg_alpha]

just tried that, not workin...this seems to work though

 

if(!preg_match('/[.](jpg)|(gif)|(png)|(jpeg)|(GIF)|(PNG)|(JPG)|(JPEG)$/', $_FILES['fupload']['name']))  {
$_SESSION['mess'] = "Images must be JPG, GIF, or PNG.";
  extract($_POST);
   header("location: picupload.php?id={$_GET['id']}");
   exit();
}

 

dadamssg, you are creating tons of alternation options / captures for nothing.

You can achieve the same pattern effect with this given example:

 

if(!preg_match('/\.(?:jpe?g|gif|png)$/i', $_FILES['fupload']['name']))  {

 

In essence, the entire alternation is a non capturing group due to the (?: .... ) syntax. In the jpe?g part, the e is optional due to the optional quantifier... Note (as MrAdam has done) that instead of putting the dot in a character class by itself, simply escape it instead. Also note the 'i' modifier I put after the closing delimiter.. this makes the pattern case insensitive..

So all in all, this pattern should match .jpg, .jpeg, .JPG, .JPEG, .gif, .GIF, .png and .PNG.