i have this regex string that i got from a website to pull emails from a file:
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])
Ive tested it in regex buddy ( regex testing software ) and it works!
when i copy and paste the regex from regex buddy to my php file, i have to escape 2 " characters to make the regex form a valid string in php.
in php i use it like this:
$file = file_get_contents(/* URL TO GET */);
$email_pattern = "(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])";
$matches = array();
if ( preg_match_all ( $email_pattern, $file, $matches ))
{
echo print_r($matches, true);
}
but i get this warning!?!?
Warning: preg_match_all() [function.preg-match-all]: Unknown modifier '#'
however this regex works in regex buddy?
Where am i going wrong???
2 things:
step 1:
You need to put delimiters ( the / before and after the regex, so that you may add modifier ):
$email_pattern = "/(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])/";
step2:
And as your in a PHP string, you'll need to escape all the special character ( like \ that must become \\ , and $ that would become \$ , etc... )
So the escape to include the regex in a PHP String should look like this:
(?:[a-z0-9!#$%&\'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&\'*+/=?^_`{|}~-]+)*|\\\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\\\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])
And you also have to escape /, as we use that caracter for the delimiter of the first step. So we need the regex to see \/, but as we express the regex in a php string, we will replace / by \\/
If I'm right -- usually I use regex buddy too to do the conversion with the PHP export tool, but now I don't have it so I've done it by hand-- it should give something LIKE this:
$email_pattern = '/(?:[a-z0-9!#$%&\'*+\/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&\'*+\/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])/';
I would also suggest that you put the string inside single quote.
I tried and...
Single quotes will give an error...
Use double quotes and the {} as delimiters // gives an error also
Related
I want to match all href values in my page content. I wrote regex for that and tested it on regex101
href[ ]*=[ ]*("|')(.+?)\1
This finds all my href values properly. If I use
href[ ]*=[ ]*(?:"|')(.+?)(?:"|')
its even better since I do not have to use certain group later.
With " and ' in regex string I cannot run the regex properly with
$matches = array();
$pattern = "/href[ ]*=[ ]*("|')(.+?)\1/"; // syntax error
$numOfMatches = preg_match_all($pattern, $pattern, $matches);
print_r($matches);
If I "escape" double quote and thus repair the syntax error I get no matches.
So - what is the correct way to apply the given regex in PHP?
Thanks for any help
Notes:
addslashes or preg_quote won't help since I need to pass legit string first
escaping all the special chars \ + * ? [ ^ ] $ ( ) { } = ! < > | : - didn't help either
EDIT: Ok, I see I really shouldn't be doing this with regex. Could you please provide some helpful DOM parsers or any other tool I 'should' use with PHP for instance ?
For your case, the following should work:
/<a\s[^>]*href=(\"??)([^\" >]*?)\\1[^>]*>(.*)<\/a>/siU
Given the nature of the WWW there are always going to be cases where the regular expression breaks down. Small changes to the patterns can fix these.
spaces around the = after href:
/<a\s[^>]*href\s*=\s*(\"??)([^\" >]*?)\\1[^>]*>(.*)<\/a>/siU
matching only links starting with http:
/<a\s[^>]*href=(\"??)(http[^\" >]*?)\\1[^>]*>(.*)<\/a>/siU
single quotes around the link address:
/<a\s[^>]*href=([\"\']??)([^\" >]*?)\\1[^>]*>(.*)<\/a>/siU
Source
I had to use this regex to make it work. Next time I will definitely try with DOM parser :)
$regexForHREF = "/href[ ]*=[ ]*(?:\"|')(.+?)(?:\"|')/";
I have the following function which as you can see, replaces certain characters in a string with the pattern, yet it only works when I enter in the pattern as a string like in the first commented out line. I put an echo in there to test what was coming back and its as it should be so I dont know whats going on! Has anyone any clues?
private function check_string( $s )
{
//return preg_replace( '/[^a-z 0-9~%\.:_\\-()"]/i', '', $s );
// a-z 0-9~%\.:_\\-()"
echo $this->permitted_uri_chars;
// /[^a-z 0-9~%\.:_\\-()"]/i
$pattern = '/[^'. $this->permitted_uri_chars .']/i';
return preg_replace( $pattern, '', $s );
}
The error I get is
Message: preg_replace(): Compilation failed: range out of order in character class at offset 18
ANSWER
Thanks to Jason McCreary
$pattern = '/[^'. preg_quote($this->config->item('permitted_uri_chars'), '/') .']+/i';
It is working in the first example because you properly escaped characters for both PHP and the Regular Expression. (i.e. \\).
When using a string, you have only escaped for PHP. So when you use this string in your Regular Expression it is no longer escaped.
This is demonstrated by the following example:
echo '/[^a-z 0-9~%\.:_\\-()"]/i';
// becomes: /[^a-z 0-9~%\.:_\-()"]/i
A few options would be:
Double escape.
Avoid the Regular Expression escaping by placing the dash at the end: /[^a-z 0-9~%.:_()"-]/
Use preg_quote() if you're going to accept strings regular expression syntax.
Note: I'd encourage you to read about escaping inside character classes.
I am trying to parse a badly formed html table:
A couple of lines of this are:
Food:</b> Yes<b><br>
Pool: </b>Beach<b></b><b><br>
Centre:</b> Yes<b><br>
After spending a lot of time on this with Xpath, I think it is probably better to split the above text into lines use preg_split and parse from there.
The pattern I think would work uses:
<\b><\br>*: <\b>
my code is as follows:
$pattern='</b></br>*:</b>';
$pattern=preg_quote($pattern,'#');
$chars = preg_split($pattern, $output);
print_r($chars);
I am getting the following error:
Delimiter must not be alphanumeric or backslash
What I am doing wrong?
Try this:
$pattern='</b></br>*:</b>';
$pattern=preg_quote($pattern,'#');
$chars = preg_split('#'.$pattern.'#', $output);
print_r($chars);
The preg_quote function just makes it safely escaped, it doesn't actually add the delimiters for you.
As other people will surely point out, using regular expressions is not a good way to parse HTML :)
Your regular expression is also not going to match what you hope. Here's a version that will probably work for your input:
$in = " Pool: </b>Beach<b></b><b><br>";
$out = explode(':', strip_tags($in));
$key = trim($out[0]);
$value = trim($out[1]);
echo "$key = $value\n";
This removes all the HTML, then splits on the colon, and then removes any surrounding whitespace.
Your pattern needs to start and end with a delimiter; looks like you're using # if I'm reading this correctly, so you should have $pattern = '#</b></br>.*:</b>#';.
Also, you're mixing things up; * is not a simple wildcard in regex. If you mean "any number of any characters," the pattern you need is .*. I've included this above.
I wrote a regex in RegExr to tackle the following string:
<?php _on*/4353452f43f43f46 xx46 _off*/ ?>
This is the Regex code:
(.*<?php.*)(.*_on.*)(.*_off.*)(.*?>)
Which is working fine here:
http://regexr.com?31ptt
But it doesn't work with PHP, I get weird errors like: "Unknown modifier '<'", etc.
What do I need to do to convert this to work with PHP?
This is my php code:
$virusstring = '(.*/<?php.*)(.*_on.*)(.*_off.*)(.*?>)';
if(preg_match($virusstring,$myfile)) {
$fixed = preg_replace($virusstring,'',$myfile);
$blah = file_put_contents($item, $fixed);
}
$myfile is just taken from the infected file that is being scanned.
Your regular expression is missing delimiters. You need to add delimiters or PHP will assume your opening ( is a delimiter:
/(.*<\?php.*)(.*_on.*)(.*_off.*)(.*\?>)/
Also, ? is a quantifier, matching 0 or 1 of the previous character. You need to escape it:
(.*<\?php.*)(.*_on.*)(.*_off.*)(.*\?>)
This seems to work fine
preg_match("/(.*<\\?php.*)(.*_on.*)(.*_off.*)(.*\\?>)/us", $searchText)
i am looking for a regex that can contain special chracters like / \ . ' "
in short i would like a regex that can match the following:
may contain lowercase
may contain uppercase
may contain a number
may contain space
may contain / \ . ' "
i am making a php script to check if a certain string have the above or not, like a validation check.
The regular expression you are looking for is
^[a-z A-Z0-9\/\\.'"]+$
Remember if you are using PHP you need to use \ to escape the backslashes and the quotation mark you use to encapsulate the string.
In PHP using preg_match it should look like this:
preg_match("/^[a-z A-Z0-9\\/\\\\.'\"]+$/",$value);
This is a good place to find the regular expressions you might want to use.
http://regexpal.com/
You can always escape them by appending a \ in front of the special characters.
try this:
preg_match("/[A-Za-z0-9\/\\.'\"]/", ...)
NikoRoberts is 100% correct.
I would only add the following suggestion: When creating a PHP regex pattern string, always use: single-quotes. There are far fewer chars which need to be escaped (i.e. only the single quote and the backslash itself needs to be escaped (and the backslash only needs to be escaped if it appears at the end of the string)).
When dealing with backslash soup, it helps to print out the (interpreted) regex string. This shows you exactly what is being presented to the regex engine.
Also, a "number" might have an optional sign? Yes? Here is my solution (in the form of a tested script):
<?php // test.php 20110311_1400
$data_good = 'abcdefghijklmnopqrstuvwxyzABCDE'.
'FGHIJKLMNOPQRSTUVWXYZ0123456789+- /\\.\'"';
$data_bad = 'abcABC012~!###$%^&*()';
$re = '%^[a-zA-Z0-9+\- /\\\\.\'"]*$%';
echo($re ."\n");
if (preg_match($re, $data_good)) {
echo("CORRECT: Good data matches.\n");
} else {
echo("ERROR! Good data does NOT match.\n");
}
if (preg_match($re, $data_bad)) {
echo("ERROR! Bad data matches.\n");
} else {
echo("CORRECT: Bad data does NOT match.\n");
}
?>
The following regex will match a single character that fits the description you gave:
[a-zA-Z0-9\ \\\/\.\'\"]
If your point is to insure that ONLY characters in this range of characters are used in your string, then you can use the negation of this which would be:
[^a-zA-Z0-9\ \\\/\.\'\"]
In the second case, you could use your regex to find the bad stuff (that you don't want to be included), and if it didn't find anything then your string pattern must be kosher, because I'm assuming that if you find one character that is not in the proper range, then your string is not valid.
so to put it in PHP syntax:
$regex = "[^a-zA-Z0-9\ \\\/\.\'\"]"
if preg_match( $regex, ... ) {
// handle the bad stuff
}
Edit 1:
I've completely ignored the fact that backslashes are special in php double-quoted strings, so here is a correcting to the above code:
$regex = "[^a-zA-Z0-9\\ \\\\\\/\\.\\'\\\"]"
If that doesn't work it shouldn't take too much for someone to debug how many of the backslashes need to be escaped with a backslash, and what other characters need also to be escaped....