How to get the URL of a webpage in PHP? - php

I need to get the URL of a website, but how do we do this in PHP?
For example there's a URL www.example.com/page.php?var=value, the URL is dynamic, I need to get the var=value portion of the URL. The URL is some other website so cannot use $_SERVER[] variables.
I cannot parse the URL since parse_url() requires an URL to be specified and I don't know the what the value of var will be, I want to fetch the URL using PHP script and then parse it.
Is there any way we can do this in PHP?

parse_url will parse the URL and return its components.
Reference: http://php.net/manual/en/function.parse-url.php
<?php
$url = 'www.example.com/page.php?var=value';
$query_string = parse_url($url, PHP_URL_QUERY );
echo $query_string;
?>
Output:
var=value

With parse_url() and parse_str() you can get the parameters:
$url = "www.example.com/page.php?var=value";
$urlParts= parse_url($url); // Separates the url
parse_str($urlParts['query'], $parameters);// Get the part you actually need it and create a array
var_dump($parameters) // Your parameters
Update:
Replace the var_dump to:
foreach($parameters as $key => $value) {
echo $key." = ".$value."<br />";
}

Related

PHP Parse URL From Current URL

I am trying to parse url and extract value from it .My url value is www.mysite.com/register/?referredby=admin. I want to get value admin from this url. For this, I have written following code. Its giving me value referredby=admin, but I want only admin as value. How Can I achieve this? Below is my code:
<?php
$url = $current_url="//".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];
setcookie('ref_by', parse_url($url, PHP_URL_QUERY));
echo $_COOKIE['ref_by'];
?>
You can use parse_str() function.
$url = "www.mysite.com/register/?email=admin";
$parts = parse_url($url);
parse_str($parts['query'], $query);
echo $query['email'];
Try this code,
$url = "www.mysite.com/register/?referredby=admin";
$parse = parse_url($url, PHP_URL_QUERY);
parse_str($parse, $output);
echo $output['referredby'];
$referred = $_GET['referredby'];
$referred = "referredby=admin";
$pieces = explode("=", $referred);
echo $pieces[1]; // admin
I don't know if it's still relevant for you, but maybe it is for others: I've recently released a composer package for parsing urls (https://www.crwlr.software/packages/url). Using that library you can do it like this:
$url = 'https://www.example.com/register/?referredby=admin';
$query = Crwlr\Url\Url::parse($url)->queryArray();
echo $query['referredby'];
The parse method parses the url and returns an object, the queryArray method returns the url query as array.
Is not a really clean solution, but you can try something like:
$url = "MYURL";
$parse = parse_url($url);
parse_str($parse['query']);
echo $referredby; // same name of the get param (see parse_str doc)
PHP.net: Warning
Using this function without the result parameter is highly DISCOURAGED and DEPRECATED as of PHP 7.2.
Dynamically setting variables in function's scope suffers from exactly same problems as register_globals.
Read section on security of Using Register Globals explaining why it is dangerous.

parse non encoded url

there is an external page, that passes a URL using a param value, in the querystring. to my page.
eg: page.php?URL=http://www.domain2.com?foo=bar
i tried saving the param using
$url = $_GET['url']
the problem is the reffering page does not send it encoded. and therefore it recognizes anything trailing the "&" as the beginning of a new param.
i need a way to parse the url in a way that anything trailing the second "?" is part or the passed url and not the acctual querystring.
Get the full querystring and then take out the 'URL=' part of it
$name = http_build_query($_GET);
$name = substr($name, strlen('URL='));
Antonio's answer is probably best. A less elegant way would also work:
$url = $_GET['url'];
$keys = array_keys($_GET);
$i=1;
foreach($_GET as $value) {
$url .= '&'.$keys[$i].'='.$value;
$i++;
}
echo $url;
Something like this might help:
// The full request
$request_full = $_SERVER["REQUEST_URI"];
// Position of the first "?" inside $request_full
$pos_question_mark = strpos($request_full, '?');
// Position of the query itself
$pos_query = $pos_question_mark + 1;
// Extract the malformed query from $request_full
$request_query = substr($request_full, $pos_query);
// Look for patterns that might corrupt the query
if (preg_match('/([^=]+[=])([^\&]+)([\&]+.+)?/', $request_query, $matches)) {
// If a match is found...
if (isset($_GET[$matches[1]])) {
// ... get rid of the original match...
unset($_GET[$matches[1]]);
// ... and replace it with a URL encoded version.
$_GET[$matches[1]] = urlencode($matches[2]);
}
}
As you have hinted in your question, the encoding of the URL you get is not as you want it: a & will mark a new argument for the current URL, not the one in the url parameter. If the URL were encoded correctly, the & would have been escaped as %26.
But, OK, given that you know for sure that everything following url= is not escaped and should be part of that parameter's value, you could do this:
$url = preg_replace("/^.*?([?&]url=(.*?))?$/i", "$2", $_SERVER["REQUEST_URI"]);
So if for example the current URL is:
http://www.myhost.com/page.php?a=1&URL=http://www.domain2.com?foo=bar&test=12
Then the returned value is:
http://www.domain2.com?foo=bar&test=12
See it running on eval.in.

I need to extract exact url using php including the id in the address

I need to extract following url using php : "http://www.website.com/profile#username". All the methods that I have tried return "http://www.website.com/profile"
Just use parse_url()
$url = 'http://www.website.com/profile#username';
$parse = parse_url($url);
print $parse['host']; // prints 'website.com'

PHP: str_replace within a word/phrase

I am trying to set up a small script that can play youtube videos but thats kinda besides the point.
I have $ytlink which equals www.youtube.com/watch?v=3WAOxKOmR90
But I want to make it become www.youtube.com/embed/3WAOxKOmR90
Currently I have tried
$result = str_replace('https://youtube.com/watch?v=', "https://youtube.com/watch?v=", $ytlink);
But this returns it as standard
I have also tried
preg_replace('/https://youtube.com/watch?v=/, '/https://youtube.com/embed/', $ytlink);
but both of these dont work.
Instead of using ugly regexes, I recommend using parse_url() with parse_str(). This allows you to be flexible in the event that you want to change something or if Youtube decides to change their URL slightly.
$url = 'https://www.youtube.com/watch?v=3WAOxKOmR90';
// Parse the URL into parts
$parsed_url = parse_url($url);
// Get the whole query string
$query = $parsed_url['query'];
// Parse the query string into parts
parse_str($query, $params);
// Get the parameter you want
$v = $params['v'];
// Now re-build the URL how you want
echo $parsed_url['scheme'].'://'.$parsed_url['host'].'/embed/'.$v;
// Outputs: https://www.youtube.com/embed/3WAOxKOmR90
This works:
$ytlink = 'www.youtube.com/watch?v=3WAOxKOmR90';
$result = str_replace('watch?v=', 'embed/', $ytlink);
echo $result;
$url = 'www.youtube.com/watch?v=3WAOxKOmR90';
echo preg_replace('/.*?v=(\w+)/i', 'www.youtube.com/embed/$1', $url);

Remove specific parameter from URL while preserving other parameters

I want remove a parameter from a URL:
$linkExample1='https://stackoverflow.com/?name=alaa&counter=1';
$linkExample2='https://stackoverflow.com/?counter=4&star=5';
I am trying to get this result:
https://stackoverflow.com/?name=alaa&
https://stackoverflow.com/?&star=5
I am trying to do it using preg_replace, but I've no idea how it can be done.
$link = preg_replace('~(\?|&)counter=[^&]*~','$1',$link);
Relying on regular expressions can screw things up sometimes..
You should use, the parse_url() function which breaks up the entire URL and presents it to you as an associative array.
Once you have that array, you can edit it as you wish and remove parameters.
Once, completed, use the http_build_url() function to rebuild the URL with the changes made.
Check the docs here..
Parse_Url Http_build_query()
EDIT
Whoops, forgot to mention. After you get the parameter string, youll obviously need to separate the parameters as individual ones. For this you can supply the string as input to the parse_str() function.
You can even use explode() with & as the delimeter to get this done.
I would recommend using a combination of parse_url() and http_build_query().
Handle it correctly! !
remove_query('http://example.com/?a=valueWith**&**inside&b=value');
Code:
function remove_query($url, $which_argument=false){
return preg_replace( '/'. ($which_argument ? '(\&|)'.$which_argument.'(\=(.*?)((?=&(?!amp\;))|$)|(.*?)\b)' : '(\?.*)').'/i' , '', $url);
}
A code example how I would grab a requested URL and remove a parameter called "name", then reload the page:
$url = $_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI']; //complete url
$parts = parse_url($url);
parse_str($parts['query'], $query); //grab the query part
unset($query['name']); //remove a parameter from query
$dest_query = http_build_query($query); //rebuild new query
$dest_url=(isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http").'://'.$parts['path'].'?'.$dest_query; //add query to host
header("Location: ".$dest_url); //reload page
parse_url() and parse_str() are buggy. Regular expressions can work but have the tendency to break. If you want to correctly deconstruct, make changes, and then reconstruct a URL, you should look at:
http://barebonescms.com/documentation/ultimate_web_scraper_toolkit/
ExtractURL() generates parse_url()-like output but does much more (and does it right). CondenseURL() takes an array from ExtractURL() and constructs a new URL from the information. Both functions are in the 'support/http.php' file.
Years later...
$_GET can be manipulated like any other array in PHP. Simply unset the key and create the http query using the http_build_query function.
// Populate _GET with sample data...
$_GET = array(
'value_a' => "A",
'key_to_remove' => "Don't delete me bro!",
'value_b' => "B"
);
// Should output everything...
// "value_a=A&key_to_remove=Don%27t+delete+me+bro%21&value_b=B"
echo "\n".http_build_query( $_GET );
// Remove the key from _GET...
unset( $_GET[ 'key_to_remove' ] );
// Should output everything else...
// "value_a=A&value_b=B"
echo "\n".http_build_query( $_GET );
This is working for me:
function removeParameterFromUrl($url, $key)
{
$parsed = parse_url($url);
$path = $parsed['path'];
unset($_GET[$key]);
if(!empty(http_build_query($_GET))){
return $path .'?'. http_build_query($_GET);
} else return $path;
}

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