I am not very good, with regular expression in php I am trying to get a reg_expression to find all file names such as /file-name-here.php and make it bold.
This expression works in Flash but not in php it also doesn't accept the '-' i'm not sure why i can't get it to work with preg_replace
/(https?://)?(www\.)?([a-zA-Z0-9_%]*)\b\.[a-z]{2,4}(\.[a-z]{2})?((/[a-zA-Z0-9_%]*)+)?(\.[a-z]*)?/g
I think you need to escape your forward slashes:
/(https?:\/\/)?(www\.)?([a-zA-Z0-9_%]*)\b\.[a-z]{2,4}(\.[a-z]{2})?((\/[a-zA-Z0-9_%]*)+)?(\.[a-z]*)?/g
Or you could use a different delimiter (in PHP, the first character is the delimiter for the regular expression):
#(https?://)?(www\.)?([a-zA-Z0-9_%]*)\b\.[a-z]{2,4}(\.[a-z]{2})?((/[a-zA-Z0-9_%]*)+)?(\.[a-z]*)?#g
Related
So I'm trying to check for match and if match, extract a variable name out of a string. The variable name should be preceded by "$" and cannot be escaped with "\", so for example "$name" should extract "name" and "\$name" or "name" shouldn't match. Heres the command:
$match = preg_match("/^(?<!\\)(\$.*)$/", $potential, $name);
I constructed and tested it using regex101.com and it works there, however, I'm getting an error from PHP saying
"preg_match(): Compilation failed: missing ) at offset 13 in ..."
and I have no clue what its referring to.
My thought is that you will need to escape certain characters to consume the regular expression in PHP
$match = preg_match('/^(?<!\\\\)(\$.*)$/', $potential, $name);
Edit: the backslash is the escape character in both Regex and PHP, you will need to doubly escape the slashes.
You've escaped a bracket:
preg_match('/^(?<!\\) <----HERE
FYI you can use several other delimiters to make your regex's more readable. Because so often we have slashes and escaped chars, then using '/' makes it hard to read. Consider using '#' or '~' or even '#' to increase readability.
Also reL your online regex tool of choice, it depends on which regular expression implementation (and version) the service uses, as to how accurate your results. I always use rubular.com (Uses PCRE) but for PHP you can use phpliveregex.com
I have made a regular expression to remove a script tag from a imported page.(used curl)
<script[\s\S]*?/script> this is my expresion
when i used it with preg_replace to remove the tag it gave me this error
Warning: preg_replace() [function.preg-replace]: Unknown modifier 'c' in C:\xampp\htdocs\get_page.php on line 21
can anyone help me
thanks
You should choose a suitable delimiter for your regular expression (preferably one that doesn't' occur anywhere in your pattern, so that you don't need to escape). For example:
"#<script[\s\S]*?/script>#"
Also, don't do that if you are trying to prevent malicious people from injecting Javascript into your page. It can easily be worked around. Use a whitelist of known safe constructs rather than trying to remove dangerous code.
PHP requires delimiters on RegExp patterns. Also, your expression can be simplified.
|<script.+/script>|
Did you wrap your regexp in forward slashes?
$str = preg_replace('/<script[\s\S]*?\/script>/', ...);
Did you surround your regular expression with a delimiter, such as /? If you didn't, you need to. If you did, and you used / (as opposed to your other choices) you'll need to escape the / in your /script, so it'll look like \/script instead.
Use the following code :
$result = preg_replace('%<script[\s\S]*?/script>%', $change_to, $subject);
iam trying to check if an user has permission to manage an group:
Expression (ou=|||) is the string I'm looking for
/^OU=|||$|,OU=|||$/i
On a string like "ou=whatever", it returns true (-:
I am sure it's a problem with the pipes, but I have no idea how to solve this.
I am using PHP 5.x with preg_match.
Pipes are metacharacters in a regular expression (meaning "or"). You need to escape them:
/^OU=\|{3}$|,OU=\|{3}$/i
Are you sure that you're using the start- and end-of-string anchors correctly? Right now, this regex will only match the strings
OU=|||
and
<any number of characters>,OU=|||
You need to escape the pipes and include some parenthesis for better readability:
/(^OU=\|\|\|$)|(,OU=\|\|\|$)/i
$has_permission = in_array('OU=|||', explode(',', $permission_string));
I get this warning from php after the change from split to preg_split for php 5.3 compatibility :
PHP Warning: preg_split(): Delimiter must not be alphanumeric or backslash
the php code is :
$statements = preg_split("\\s*;\\s*", $content);
How can I fix the regex to not use anymore \
Thanks!
The error is because you need a delimiter character around your regular expression.
$statements = preg_split("/\s*;\s*/", $content);
Although the question was tagged as answered two minutes after being asked, I'd like to add some information for the records.
Similar to the way strings are delimited by quotation marks, regular expressions in many languages, such as Perl or JavaScript, are delimited by forward slashes. This will lead to expressions looking like this:
/\s*;\s*/
This syntax also allows to specify modifiers:
/\s*;\s*/Ui
PHP's Perl-compatible regular expressions (aka preg_... functions) inherit this. However, PHP itself doesn't support this syntax so feeding preg_split() with /\s*;\s*/ would raise a parse error. Instead, you enclose it with quotes to build a regular string.
One more thing you must take into account is that PHP allows to change the delimiter. For instance, you can use this:
#\s*;\s*#Ui
What is it good for? It simplifies the use of forward slashes inside the expression since you don't need to escape them. Compare:
/^\/home\/.*$/i
#^/home/.*$#i
If you don't like delimiters, you can use T-Regx tool:
pattern("\\s*;\\s*")->split($content):
You can also use Pattern::of("\\s*;\\s*")->split()
I have an API call that essentially returns the HTML of a hosted wiki application page. I'm then doing some substr, str_replace and preg_replace kung-fu to format it as per my sites style guides.
I do one set of calls to format my left nav (changing a link to pageX to my wikiParse?page=pageX type of thing). I can safely do this on the left nav. In the body text, however, I cannot safely assume a link is a link to an internal page. It could very well be a link to an external resource. So I need to do a preg_replace that matches href= that is not followed by http://.
Here is my stab at it:
$result = preg_replace('href\=\"(?!http\:\/\/)','href="bla?id=',$result);
This seems to strip out the entire contents on the page. Anyone see where I slipped up? I don't think I'm too far off, just can't see where to go next.
Cheers
The preg_* functions expect Perl-Compatible Regular Expressions (PCRE). The structural difference to normal regular expressions is that the expression itself is wrapped into delimiters that separate the expression from possible modifiers. The classic delimiter is the / but PHP allows any other non-alphanumeric character except the backslash character. See also Intruduction to PCRE in PHP.
So try this:
$result = preg_replace('/href="(?!http:\/\/)/', 'href="bla?id=', $result);
Here href="(?!http://) is the regular expression. But as we use / as delimiters, the occurences of / inside the regular expression must be escaped using backslashes.
Your regexp is missing starting and ending delimiters (by default '/');
$result = preg_replace('/href\=\"(?!http\:\/\/)/','href="bla?id=',$result);