I am trying to understand this one line of code below:
str_replace('../', '', $route);
Basically it says replace '../' with nothing in $route
$route = 'information/information&information_id=4';
from the url 'index.php?route=information/information&information_id=4'
But there is no ../ in the $route variable. Is it some sort of regex? If yes, what does it exactly do. Thanks guys.
You are correct in thinking that it replaces "../" with an empty string. It is not regex. There is no occurence of it in your example, but there could be.
It might be used for some sort of security to prevent you from going back up the directory structure from the document root.
If there's no ../ in the string, this will replace nothing. It's not a regex (see preg_replace() for that. It's just precaution against someone trying to pass invalid path (starting with ../), which could potentially be an attempt of accessing files outside of webserver's document root (in other words, a hacking attempt).
Related
I have downloaded some PHP code because I want to modify it and use it for my project.
I have this line of code:
$uri=rtrim(dirname($_SERVER['PHP_SELF']),'/\\');
I know the $_SERVER['PHP_SELF'] it is a superglobal variable that returns the file name of the current running script.
But I do not know why rtrim is used!
Can someone shortly explain to me?
From the PHP doc:
rtrim — Strip whitespace (or other characters) from the end of a
string
To explain more :
_SERVER['PHP_SELF']:
will return The filename of the currently executing script, relative to the document root. For instance, $_SERVER['PHP_SELF'] in a script at the address http://example.com/foo/bar.php would be /foo/bar.php
And the dirname will Returns a parent directory's path like src/foo/bar.php.
To ensure that there is no special caracter inside , the rtrim will strip whitespace (or other characters) from the end of a string.
Hope this help you.
Does PHP have a native function that returns the full URL of a file you declare with a relative path? I need to get: "http://www.domain.com/projects/test/img/share.jpg" from "img/share.jpg" So far I've tried the following:
realpath('img/share.jpg');
// Returns "/home/user/www.domain.com/projects/test/img/share.jpg"
I also tried:
dirname(__FILE__)
// Returns "/home/user/www.domain.com/projects/test"
And this answer states that the following can be tampered with client-side:
"http://'.$_SERVER[HTTP_HOST].$_SERVER[REQUEST_URI].'img/share.jpg"
plus, my path will vary depending on whether I'm accessing from /test/index.php or just test/ without index.php and I don't want to hard-code whether it's http or https.
Does anybody have a solution for this? I'll be sending these files to another person who will upload to their server, so the folder structure will not match "/home/user/www.domain.com/"
echo preg_replace(preg_quote($_SERVER['DOCUMENT_ROOT']), 'http://www.example.com/', realpath('img/share.jpg'), 1);
Docs: preg_replace and preg_quote.
The arguments of preg_replace:
preg_quote($_SERVER['DOCUMENT_ROOT']) - Takes the document root (e.g., /home/user/www.domain.com/) and makes it a regular expression for use with preg_replace.
'http://www.example.com/' - the string to replace the regex match with.
realpath('img/share.jpg') - the string for the file path including the document root.
1 - the number of times to replace regex matches.
How about
echo preg_replace("'". preg_quote($_SERVER['DOCUMENT_ROOT']) ."'",'http://www.example.com/', realpath('img/share.jpg'), 1);
I'm trying to match files of the following structure in PHP.
Input:
filename.ext1
filename.ext1.ext2
filename.ext3.ext2.ext1
filename.ext4.ext2.ext1.ext4
file name with spaces and no way of knowing how long.ext1
file name with spaces and no way of knowing how long.ext1.ext2
file name with spaces and no way of knowing how long.ext2.ext1.ext3
file name with spaces and no way of knowing how long.ext3.ext1.ext4.ext3
Output:
filename
filename
filename
filename
file name with spaces and no way of knowing how long
file name with spaces and no way of knowing how long
file name with spaces and no way of knowing how long
file name with spaces and no way of knowing how long
What I've already attempted (doesn't work of course and I already understand why):
^(?P<basename>.*)(\.ext4)|(\.ext3)|(\.ext2)|(\.ext1).*$
I'd like to extract the base name of the file and basically strip all extensions, because there's no way of knowing in which order they may appear. I've tried several solutions presented here but they did not work for me. The extensions could be anything alphanumeric of any length.
I'm fairly new to regular expressions and am confused that apparently you cannot simply search forward to the first dot and remove it including everything that comes after.
To learn, I'd also love to see how to do the reverse and just match all the extensions including the first dot.
Update:
I didn't think about file names that contain dots. So obviously my thinking regarding "searching forward" is flawed. Does anyone have a solution for the case
file name with spaces and no. way of knowing how long.ext3.ext1.ext4.ext3
or even
file name with spaces and no way of knowing.how.long.ext3.ext1.ext4.ext3
The latter one would quite possibly only work when certain extensions are given. So please assume ext1-4 are given but are in an unpredictable sequence.
Quick and dirty:
preg_replace("/\.(ext1|ext2|ext3|ext4)/i", "", $filename)
There's no need to use regular expressions for this; PHP has the buildin function basename() for that
Does something simple like this works for you....
^[^.]*
Basically it just matches string before first dot.
This regex should work for you:
^.+?(?=\.[^.]*$)
Online Demo: http://regex101.com/r/uT2oK5
This will find file names before very last dot only. See all the examples included in the link.
am confused that apparently you cannot simply search forward to the first dot and remove it including everything that comes after.
Since regexes are read from left to right, looking for a single dot will lead you straight to the first dot. That said, you would thus be able to use:
preg_replace("/\..*/", "", $filename);
.* matches any characters except newlines.
If the filename has dots, this obviously won't work, since part of the filename will then be removed.
As per update, if you have the specific extensions, you can use something like this:
preg_replace("/(?:\.ext[1-4])+$/m", "", $filename);
regex101 demo
In a broader perspective, you could use something like this if you have an array of extensions at your disposition:
$exts = array(".ext1", ".ext2", ".ext3", ".ext4");
$result = preg_replace("/(?:". preg_quote(join("|",$exts)) .")+$/m", "", $filename);
.*(?=\.)
Try this? Will match all before the last dot even if theres a dot in the file name
This is easy with just plain old php functions. No need for fancy regex.
$name = substr($filename, 0, strpos($filename, '.'));
This won't work for filenames which have a . like your updated example, however in order to achieve this you would likely need to know in advance the extensions which you are likely to encounter.
I am looking to strip away a part of the following url yet have no experience with regex or if that's even what I would use.
I have this url:
/var/www/wordpress/wp-content/themes/Aisis-Framework/CoreTheme/AdminPanel/Template/Form/Update.php
I would like to strip away everything to form:
CoreTheme/AdminPanel/Template/Form/Update.php
Is there an easy way to do this, and one that is done such that the amount of content before "CoreTheme" could be x characters long, where x is any number.
It should also not match on the word CoreTheme as it might be any name, it should also not match on Aisis-Framework as that could also be any name...
how ever it is safe to assume that anything after CoreTheme is static. The above string will be turned into, using string replace:
CoreTheme_AdminPanel_Template_Form_Update.php
As I have done in this piece of code:
$class_name = str_replace('/', '_', $path . $name);
where path is, in my solution, CoreTheme/AdminPanel/Template/Form/Update.php and $name is Update
If "/var/www/wordpress/wp-content/themes/Aisis-Framework/" is constant I would just do:
str_replace("/var/www/wordpress/wp-content/themes/Aisis-Framework/","",$path);
Otherwise you would need something constant to get a pattern of, like the number of directories deep or a specific pattern to match.
I am trying to get the page or last directory name from a url
for example if the url is: http://www.example.com/dir/ i want it to return dir or if the passed url is http://www.example.com/page.php I want it to return page Notice I do not want the trailing slash or file extension.
I tried this:
$regex = "/.*\.(com|gov|org|net|mil|edu)/([a-z_\-]+).*/i";
$name = strtolower(preg_replace($regex,"$2",$url));
I ran this regex in PHP and it returned nothing. (however I tested the same regex in ActionScript and it worked!)
So what am I doing wrong here, how do I get what I want?
Thanks!!!
Don't use / as the regex delimiter if it also contains slashes. Try this:
$regex = "#^.*\.(com|gov|org|net|mil|edu)/([a-z_\-]+).*$#i";
You may try tho escape the "/" in the middle. That simply closes your regex. So this may work:
$regex = "/.*\.(com|gov|org|net|mil|edu)\/([a-z_\-]+).*/i";
You may also make the regex somewhat more general, but that's another problem.
You can use this
array_pop(explode('/', $url));
Then apply a simple regex to remove any file extension
Assuming you want to match the entire address after the domain portion:
$regex = "%://[^/]+/([^?#]+)%i";
The above assumes a URL of the format extension://domainpart/everythingelse.
Then again, it seems that the problem here isn't that your RegEx isn't powerful enough, just mistyped (closing delimiter in the middle of the string). I'll leave this up for posterity, but I strongly recommend you check out PHP's parse_url() method.
This should adequately deliver:
substr($s = basename($_SERVER['REQUEST_URI']), 0, strrpos($s,'.') ?: strlen($s))
But this is better:
preg_replace('/[#\.\?].*/','',basename($path));
Although, your example is short, so I cannot tell if you want to preserve the entire path or just the last element of it. The preceding example will only preserve the last piece, but this should save the whole path while being generic enough to work with just about anything that can be thrown at you:
preg_replace('~(?:/$|[#\.\?].*)~','',substr(parse_url($path, PHP_URL_PATH),1));
As much as I personally love using regular expressions, more 'crude' (for want of a better word) string functions might be a good alternative for you. The snippet below uses sscanf to parse the path part of the URL for the first bunch of letters.
$url = "http://www.example.com/page.php";
$path = parse_url($url, PHP_URL_PATH);
sscanf($path, '/%[a-z]', $part);
// $part = "page";
This expression:
(?<=^[^:]+://[^.]+(?:\.[^.]+)*/)[^/]*(?=\.[^.]+$|/$)
Gives the following results:
http://www.example.com/dir/ dir
http://www.example.com/foo/dir/ dir
http://www.example.com/page.php page
http://www.example.com/foo/page.php page
Apologies in advance if this is not valid PHP regex - I tested it using RegexBuddy.
Save yourself the regular expression and make PHP's other functions feel more loved.
$url = "http://www.example.com/page.php";
$filename = pathinfo(parse_url($url, PHP_URL_PATH), PATHINFO_FILENAME);
Warning: for PHP 5.2 and up.