preg_match validation.

[daydreamer]

I need to validate a text area using php.

I want to allow numbers, text, and these characters only:

#=|/€$£^"&;_,?.@-)%+*\[]><]+$/

 

<?php
if(!preg_match('/^[a-z0-9#=|/€$£^"&;_,?.@-)%+*\[]><]+$/'), $_POST['message']) )
?>

 

This is what i have so far but all i get is:

 Parse error: syntax error, unexpected ',' in C:\wamp\www\send.php on line 38

(the above line of code is line 38).

 

Also the original php codes does not have those numbers &#8364;$&#163 in the string, the phpfreaks forum adds them for some reason.

 

I dont have much experience using the preg_match function, any help would be good!

 

cheers.

[discomatt]

You have an unnecessary ')'

 

!preg_match('/^[a-z0-9#=|/€$£^"&;_,?.@-)%+*\[]><]+$/', $_POST['message'])

 

You may also want to use the 'i flag for case insensitivity

[nrg_alpha]

It seems you have a few inherent problems with your pattern.

 

a) Notice this part of your pattern: @-:  That dash, I assume is meant to be a dash.. but dashes in a character class need to be set first, otherwise, you are telling regex engine that this is a range (much like a-z).

b) I think you need to escape your parethesis characters, as well as your square brackets.. otherwise regex thinks this is a group and a character class respectively.

c) you need to escape your '/' character, because you are using these as delimiters as well.

 

So here is the pattern corrected of those issues:

if(!preg_match('/^[-a-z0-9#=|\/€$£^"&;_,?.@:\(\)%+*\[\]><]+$/'), $_POST['message']))

[daydreamer]

thanks for the case sensitive suggestion, i hadn't even noticed!

 

ive taken the extra bracket away but same problem.

 

I think it has something to do with the £.

 

I now have this:

if(!preg_match('/^[a-z0-9!?+&%\,\'@#() \$\"]+$/i', $_POST['message'])

 

it works, but I would like to include £ and €.

 

Also, another problem I have is that i need to skip white space, because when I press enter in the textfield this shows up as an error (because of the newline/white space).

 

Ive read that you can use the s flag :"s - Includes New line".

 

How do i do this with the i flag as well? Will this fix my problem?

 

Thanks

[daydreamer]

thanks nrg_alpha,

 

your explanation did help, but the validation still shows as error when i type £ and also $. I think most of the other symbols are fine though.

 

one main problem i still have is when i type enter/return, that shows up as an error and i need to allow them.

 

 

[nrg_alpha]

thanks nrg_alpha,

 

your explanation did help, but the validation still shows as error when i type £ and also $. I think most of the other symbols are fine though.

 

one main problem i still have is when i type enter/return, that shows up as an error and i need to allow them.

 

You have those errors because you are missing those elements in your last snippet you provided..

try:

 

if(!preg_match('/^[a-z0-9!?+&\/£%,\'@#()\$\"]+$/i', $str))

[thebadbad]

This should work, and allows linebreaks (by removing them before the validation):

 

<?php
$_POST['message'] = str_replace("\n", '', str_replace("\r", '', $_POST['message']));
if (!preg_match('~^[-0-9a-z#=|/€$£"&;_,?.@)%+*^[\]>\\\<]+$~iD', $_POST['message'])) {
echo 'Error!';
}
?>

 

A backslash is escaped with two backslashes (that's what worked for me at least) and the only other escaped character is ].

 

If you also wanna allow single quotes, just add one after the double quote.

[thebadbad]

Of course you don't want to remove the linebreaks from the original string, just do it for the string to test. E.g. use this instead:

 

<?php
$string = str_replace("\n", '', str_replace("\r", '', $_POST['message']));
if (!preg_match('~^[-0-9a-z#=|/€$£"&;_,?.@)%+*^[\]>\\\<]+$~iD', $string)) {
//error
} else {
//$_POST['message'] is OK, process it further
}
?>

[daydreamer]

nrg_alpha, i was talking about the first one you gave me, tryd them both but both give errors when i type £ or €, which they should be allowing!

 

Oh well, its not too important i have the majority of the symbols which are useful. Thanks.

 

thebadbad, thanks, but i found this somewhere and it works pretty well:

 

 

<?php function clean($str){//Removes leading and trailing white space and removes any multiple white space in the source string
return preg_replace('/(\s\s+)/', ' ', trim($str));
} ?>

 

but your example still wont except £ or €!

[thebadbad]

My code does accept € and £ - you must have some problems with the character encoding. Be sure that the PHP file and the actual HTML handling the form use the same character encoding (UTF-8 is recommended).

 

If you want to allow spaces, add \s inside the character class (square brackets), after the underscore for example.

[ibechane]

For special characters, you might consider the unicode reprentation \uXXXX, where XXXX is a 4-digit number (with filler-zeros if necessary) that represents the unicode character.

 

Here is a chart of the codes: http://www.geocities.com/Athens/Academy/4038/graph/fontset.htm

 

So, for instance, the code for the pound symbol is 163, so try replacing the pound symbol with \u0163 in your regex string.

[daydreamer]

ok thanks.