This question already has an answer here:
Reference - What does this regex mean?
(1 answer)
Closed 7 years ago.
I am using this library with this line of text
#asdfasdf #日本語 スペース #漢字 ＃日本語 あ http://url file:///url「おくむら」最高ー！…
And it gives me right values
#asdfasdf #日本語
But in code there is % in regex
'%(\A#(\w|(\p{L}\p{M}?)|-)+\b)|((?<=\s)#(\w|(\p{L}\p{M}?)|-)+\b)|((?<=\[)#.+?(?=\]))%u'
What does this percent sign do?
In iOS it works without percent sign like this.
"(\\A#(\\w|(\\p{L}\\p{M}?)|-)+\\b)|((?<=\\s)#(\\w|(\\p{L}\\p{M}?)|-)+\\b)|((?<=\\[)#.+?(?=\\]))"
In php it gives me error: preg_match_all(): Unknown modifier '|'
What does this percent sign do?
Nothing, it is the delimiter to separate the regex from the additional options. They are required in the preg_* library, see http://php.net/manual/en/regexp.reference.delimiters.php.
Note that if you don't use the % in your regex, the ( ... ) will be used as the delimiter, leading to an error when you need to use them in your regex itself and you don't escape them.
Which is happening here in your case:
(\\A#(\\w|(\\p{L}\\p{M}?)|
^ Here the regex engine thinks you are closing the expression
Related
This question already has answers here:
How can I convert ereg expressions to preg in PHP?
(4 answers)
Closed 2 years ago.
I found one PHP script for get a database backup, there use this expression to do something, that script show call to undefined function ereg_replace() this error, if i remove this line script is working fine...
how to replace this function $row[$j] = ereg_replace("\n","\\n",$row[$j]); to that script working finely,
Can anyone assist me..
ereg_replace deprecated and remove from newer versions of php (7 and up).
You will have to update your code to use preg_replace
$row[$j] = preg_replace("#\n#","\\n",$row[$j]);
One of the differences between ereg_replace() and preg_replace() is that the pattern must be enclosed by delimiters: delimiter + pattern + delimiter, in this case we are using # so we don't have to escape / that is the usual that is used.
Valid Delimiters:
/, #, ~, +, %, #, ! , <, >
Reference from php.net
hope it helps.
This question already has answers here:
How do I match any character across multiple lines in a regular expression?
(26 answers)
Closed 3 years ago.
Given a fairly simple regex, I'd like to match a text between to delimiters:
___MANUAL_TICKET___
###_CLIENT_START_###
TEST
###_CLIENT_END_###
###_PROBLEM_START_###
TEST2
###_PROBLEM_END_###
###_EMAIL_START_###
xyz#test.com
###_EMAIL_END_###
To get the client I am using this regex:
###_CLIENT_START_###\s(.*?)\s###_CLIENT_END_###
which works as seen HERE.
But when I use it in my PHP Code it does not find any matches:
preg_match('####_CLIENT_START_###\s(.*?)\s###_CLIENT_END_####', $source, $matches);
(tried different regex delimiter such as / and ~, same result)
What am I doing wrong?
Note that the dot (.) by default matches any symbol but the line feed (See the documentation).
Since you have multiple line input, you need to use the PCRE_DOTALL option, which can be enabled just adding symbol s at the very end of the pattern
preg_match('####_CLIENT_START_###\s(.*?)\s###_CLIENT_END_####s', $source, $matches);
^ here
This question already has answers here:
allow parentheses and other symbols in regex
(5 answers)
Closed 7 years ago.
I have few questions regarding preg_match in php.
if(preg_match('#[^0-9 -&()+#._A-Za-z]#', $input)){
$errors .= 'Sorry, username can\'t contain those characters.<br>';
}
This is my preg_match. I am kinda new to these codes. I have red that its better to use # on the end and beginning than / for unknown reason xD
Anyone knows what is up with that?
My main problem is that this preg_match actually let strings with % (percent signs) through and it shouldn't. Why? and how to stop that?
Another question is this preg_match code good?
It works fine (except % part) but can it fail?
Thank you :)
this preg_match actually let strings with "%" (percent signs) through and it shouldn't. Why?
That is due to unescaped hyphen in the middle of your regex:
'#[^0-9 -&()+#._A-Za-z]#'
--------^
- is acting as range from space (32) to & (38) thus matching anything in between including % ( 37).
It should be used as:
'#[^-0-9 &()+#._A-Za-z]#'
Or
'#[^-\w &()+#.]#'
However without anchors this character class will match only one character. You should use:
'#^[^-\w &()+#.]+$#'
This question already has answers here:
Warning: preg_replace(): Unknown modifier
(3 answers)
Closed 3 years ago.
trying to fix this regex. Its supposed to find any hyperlinks in a string and put anchor tags around them. Keeps coming back, unkown identifier '+'. I thought the plus sing was part of regex?
<?php
//replace links with clickable links
// match protocol://address/path/
$comments = preg_replace("[a-zA-Z]+://([.]?[a-zA-Z0-9_/-])*", "\\0", $comments);
// match www.something
$comments = preg_replace("(^| )(www([.]?[a-zA-Z0-9_/-])*)", "\\1\\2", $comments);
?>
any help appreciated.
A PCRE patterns (that's what you give to preg_replace) needs to be enclosed by delimiters:
~[a-zA-Z]+://([.]?[a-zA-Z0-9_/-])*~
Here the ~ are the delimiters. I used this char because it doesn't occur in the rest of the regex.
To explain the error: PCRE thinks that [ is the delimiter (as the first char always is the delimiter). So when it find the corresponding closing delimiter ] is considers everything after it a modifier. And as there is no + modifier you get an error ;)
try replacing
"[a-zA-Z]+://([.]?[a-zA-Z0-9_/-])*", "\\0"
with
r'[a-zA-Z]+://([.]?[a-zA-Z0-9_/-])*', '\\0'
This question already has answers here:
Warning: preg_replace(): Unknown modifier
(3 answers)
Closed 3 years ago.
Im trying to search for something on a page but i keep getting this silly error
this is the error i am getting
Warning: preg_match() [function.preg-match]: Unknown modifier 'd'
this is the code im using
$qa = file_get_contents($_GET['url']);
preg_match('/Click here/',$qa,$result);
And $_GET['url'] can eqaul many things but in one case it was http://freegamesforyourwebsite.com/game/18-wheeler--2.html
the the html of that url basically
Anyone got a clue :S ? I dont even know where to start cus i dont know what a modifire is and the php.net site is no help
thankyou !
You need to escape the '/' before download.php otherwise it thinks you are ending your regex and providing 'd' as a modifier for your regex. You will also need to escape the next '/' in the ending anchor tag.
preg_match('/<a href="\/download.php\?g=(?P<number>.+)">Click here<\/a>/',$qa,$result);
You have to escape your pattern delimiters or use different ones:
# v- escape the '/'
preg_match('/Click here/',$qa,$result);
# v- use hatch marks instead
preg_match('#Click here#',$qa,$result);
Your regular expression needs to be escaped correctly.
It should be:
'/<a href="\/download.php\?g=(?P<number>.+)">Click here<\/a>/'
The problem is that your regular expression is delimited by / characters, but also contains / characters as data. What it's complaining about is /download -- it thinks the / has ended your regular expression and the d that follows is a modifier for your regular expression. However, there is no such modifier d.
The easiest solution is to use some character that is not contained in the regex to delimit it. In this case, # would work well.
preg_match('#Click here#',$qa,$result);