Question

So I’m attempting to remove specific parameters from the URL query string that are predefined in an array. Here’s what I have so far:

<?php
// Construct the current page URL
$host     = $_SERVER['HTTP_HOST'];
$script   = $_SERVER['SCRIPT_NAME'];
$params   = $_SERVER['QUERY_STRING'];
$currentUrl = 'http://' . $host . $script . '?' . $params;

// Store all URL parameters into an array (HOST, PATH, QUERY, etc)
$url_params = array();
$url_params = parse_url($currentUrl);

// Create an array to store just the query string, breaking them apart
$params_array = explode('&', $url_params['query']);

// Array holding URL parameters that we want to remove
$params_to_remove = array("param1", "param2", "param3", "param4", "param5");


$location = 0;
// Loop through and remove parameters found in PARAMS_TO_REMOVE array
for($x = 0; $x < count($params_to_remove); $x++) {
    if(in_array($params_to_remove[$x], $params_array)) {
        $location = array_search($params_to_remove[$x], $params_array);
        unset($params_array[$location]);
    }
}

// Print array after unwanted parameters were removed
print_r($params_array);
echo '<br /><br />';

// Construct a new array holding only the parameters that we want
$clean_params_array = array();
for($z = 0; $z < count($params_array); $z++) {
    if($params_array[$z] != '') array_push($clean_params_array, $params_array[$z]);
}

// Print clean array
print_r($clean_params_array);
echo '<br />';

// Construct the new URL
// If there are paramters remaining in URL reconstruct them
if(count($clean_params_array) > 0) {
    $final_url = 'http://www.example.com' . $url_params['path'] . '?';
    for($y = 0; $y < count($clean_params_array); $y++) {
        $final_url .= $clean_params_array[$y] . '&';
    }
    // Trim off the final ampersand
    $final_url = substr($final_url, 0, -1);
}
// No parameters in final URL
else $final_url = 'http://www.example.com' . $url_params['path'];

// Print final URL
echo '<br />' . $final_url;
?>

Here’s the output:

Using http://www.example.com/test.php?apple&banana&orange&param1&strawberry&param2&pineapple

Array ( [0] => apple [1] => banana [2] => orange [4] => strawberry [6] => pineapple ) 

Array ( [0] => apple [1] => banana [2] => orange [3] => strawberry ) 

http://www.example.com/test.php?apple&banana&orange&strawberry

As you can see I’m losing the last parameter. I also feel as if I’m being too verbose…where am I going wrong?

Answer 1

$new_url = "http://".$_SERVER['HTTP_HOST'].$_SERVER['SCRIPT_NAME']."?".implode("&",array_diff(explode("&",$_SERVER['QUERY_STRING']),Array("param1","param2","param3","param4","param5")));

One-liner 😉

Although you’d probably be better off taking that Array(...) out of there and defining it as a variable beforehand, so it’s easier to read.