Beautiful way to remove GET-variables with PHP?

Jens Törnell picture Jens Törnell · Aug 9, 2009 · Viewed 152.2k times · Source

I have a string with a full URL including GET variables. Which is the best way to remove the GET variables? Is there a nice way to remove just one of them?

This is a code that works but is not very beautiful (I think):

$current_url = explode('?', $current_url);
echo $current_url[0];

The code above just removes all the GET variables. The URL is in my case generated from a CMS so I don't need any information about server variables.

Answer

Justin picture Justin · Aug 9, 2009

Ok, to remove all variables, maybe the prettiest is

$url = strtok($url, '?');

See about strtok here.

Its the fastest (see below), and handles urls without a '?' properly.

To take a url+querystring and remove just one variable (without using a regex replace, which may be faster in some cases), you might do something like:

function removeqsvar($url, $varname) {
    list($urlpart, $qspart) = array_pad(explode('?', $url), 2, '');
    parse_str($qspart, $qsvars);
    unset($qsvars[$varname]);
    $newqs = http_build_query($qsvars);
    return $urlpart . '?' . $newqs;
}

A regex replace to remove a single var might look like:

function removeqsvar($url, $varname) {
    return preg_replace('/([?&])'.$varname.'=[^&]+(&|$)/','$1',$url);
}

Heres the timings of a few different methods, ensuring timing is reset inbetween runs.

<?php

$number_of_tests = 40000;

$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$starttime = $mtime;

for($i = 0; $i < $number_of_tests; $i++){
    $str = "http://www.example.com?test=test";
    preg_replace('/\\?.*/', '', $str);
}
$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$endtime = $mtime;
$totaltime = ($endtime - $starttime);
echo "regexp execution time: ".$totaltime." seconds; ";

$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$starttime = $mtime;
for($i = 0; $i < $number_of_tests; $i++){
    $str = "http://www.example.com?test=test";
    $str = explode('?', $str);
}
$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$endtime = $mtime;
$totaltime = ($endtime - $starttime);
echo "explode execution time: ".$totaltime." seconds; ";

$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$starttime = $mtime;
for($i = 0; $i < $number_of_tests; $i++){
    $str = "http://www.example.com?test=test";
    $qPos = strpos($str, "?");
    $url_without_query_string = substr($str, 0, $qPos);
}
$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$endtime = $mtime;
$totaltime = ($endtime - $starttime);
echo "strpos execution time: ".$totaltime." seconds; ";

$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$starttime = $mtime;
for($i = 0; $i < $number_of_tests; $i++){
    $str = "http://www.example.com?test=test";
    $url_without_query_string = strtok($str, '?');
}
$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$endtime = $mtime;
$totaltime = ($endtime - $starttime);
echo "tok execution time: ".$totaltime." seconds; ";

shows

regexp execution time: 0.14604902267456 seconds; explode execution time: 0.068033933639526 seconds; strpos execution time: 0.064775943756104 seconds; tok execution time: 0.045819044113159 seconds; 
regexp execution time: 0.1408839225769 seconds; explode execution time: 0.06751012802124 seconds; strpos execution time: 0.064877986907959 seconds; tok execution time: 0.047760963439941 seconds; 
regexp execution time: 0.14162802696228 seconds; explode execution time: 0.065848112106323 seconds; strpos execution time: 0.064821004867554 seconds; tok execution time: 0.041788101196289 seconds; 
regexp execution time: 0.14043688774109 seconds; explode execution time: 0.066350221633911 seconds; strpos execution time: 0.066242933273315 seconds; tok execution time: 0.041517972946167 seconds; 
regexp execution time: 0.14228296279907 seconds; explode execution time: 0.06665301322937 seconds; strpos execution time: 0.063700199127197 seconds; tok execution time: 0.041836977005005 seconds; 

strtok wins, and is by far the smallest code.