Help with preg_match

unk

I unfortently don't know the first thing when it comes to regular expressions.

My problem is I want to find a match of a file type in a string of file types.

Example of string:
.jpeg|.jpg|.gif|.png

Example of file:
mypicture.gif

Any help would be appreciated, thanks in advance.

TheIceman5

have u even bothered to search for a answer?? doing a search on here should tell u all u need to know plus more.

unk

I wouldn't have bothered registering, then making a thread if I hadn't...Thanks for your help.

tekky

Originally posted by TheIceman5
have u even bothered to search for a answer?? doing a search on here should tell u all u need to know plus more.

more importantly, what have you tried that didnt work?

example of not working code + the input string you are trying to match will get you far in life 😉 (atleast in life at phpbuilder.com 😛)

unk

I've tried this:

if (!preg_match( '/|/',$allowed_files))  {
$content = "That file is not one of the allowed types<br>
Please <a href=\"javascript:history.back()\">try</a> again.";

It's obviously not right because it doesn't work at all. Like I said, I don't know the first thing about regular expressions.

tekky

getting closer.... what does $allowed_files look like?

know what you are trying to match AND what you are trying to match AGAINST is kind of key here...

what line are you feeding preg_match to scan...

what values are you comparing against...

do you get errors, no results, blank page, 3 clowns laughing at you? what?

unk

The string is in my first post, but here it is again:

$allowed_files = ".jpeg|.jpg|.gif|.png";

The variable it's checking it against is $img_name, for example $img_name = "myfile.gif";

What's happening when I try this is essentially nothing. I get no errors, but it doesn't function either in that anything can be put against the string and it will pass. For example a .txt file would be allowed when it shouldn't be.

I'm sorry if my first post was too vague.

tekky

Originally posted by unk
The string is in my first post, but here it is again:

$allowed_files = ".jpeg|.jpg|.gif|.png";

The variable it's checking it against is $img_name, for example $img_name = "myfile.gif";

What's happening when I try this is essentially nothing. I get no errors, but it doesn't function either in that anything can be put against the string and it will pass. For example a .txt file would be allowed when it shouldn't be.

I'm sorry if my first post was too vague.

no worries, you've got it covered now 🙂

try

if (eregi($allowed_files, $img_name))
     echo "$img_name is fine!";
else
     echo "$img_name isnt allowed!";

unk

I feel like an ass because now I see it was pretty simple. But thank you very much, you have no idea how happy this makes me now that this part of my script is out of the way.

tekky

Originally posted by unk
I feel like an ass because now I see it was pretty simple. But thank you very much, you have no idea how happy this makes me now that this part of my script is out of the way.

hehe, no problem, although you may want to test this...

I believe that above will also match this.jpg.somethingelse

the I think to fix taht you would need to add $ after each extention in the list you have

HalfaBee

The . should be escaped

'.gif' or "\." because the . means any character.
The string should look like '.gif|jpg|jpeg$'

HalfaBee

tekky

Heh, I was close to right in my final rant 😃

(still learning regexps :o)

HalfaBee

If someone says they know all about regex - don't beleive them.

Should have been
.(gif|jpg|jpeg)$

I have a little script that has a form with two inputs and submits to itself then says good or bad for the test.
It keeps the regex and sample data so you can keep editing it until it works properly.
Something like this

extract( $_GET );
if( !isset($regex) )
    $regex= "." ; // startup value if needed
else
    $regex=stripslashes( $regex );

echo "<form>
<input name=test value='$test' ><br>
<input name=regex value='$regex' size=100>   <br>
<input type=submit>
</form>";

if( !ereg( $regex,$test ) ) {
print("your test is invalid");
}
else
echo "Good test";

HalfaBee

tekky

Originally posted by HalfaBee
.....
explode( $_GET );
.....
.....
HalfaBee [/B]

this baffles me.... hehe 😛

must be a new version of explode() 😃

HalfaBee

Ooops extract()

HalfaBee