better way to replace query string value in a given url

Question

Okay.. so basically, say we have a link:

$url = \"http://www.site.com/index.php?sub=Mawson&state=QLD&cat=4&page=2&sort=z\";

Answer 1

<?php
function change_query ( $url , $array ) {
    $url_decomposition = parse_url ($url);
    $cut_url = explode('?', $url);
    $queries = array_key_exists('query',$url_decomposition)?$url_decomposition['query']:false;
    $queries_array = array ();
    if ($queries) {
        $cut_queries   = explode('&', $queries);
        foreach ($cut_queries as $k => $v) {
            if ($v)
            {
                $tmp = explode('=', $v);
                if (sizeof($tmp ) < 2) $tmp[1] = true;
                $queries_array[$tmp[0]] = urldecode($tmp[1]);
            }
        }
    }
    $newQueries = array_merge($queries_array,$array);
    return $cut_url[0].'?'.http_build_query($newQueries);
}
?>

Use like this :

<?php
    echo change_query($myUrl, array('queryKey'=>'queryValue'));
?>

I do that this morning, it seems to work in all case. You can change / add more than one query, with the array ;)

Answer 2

<?php
//current url: http://localhost/arters?sub=Mawson&state=QLD&cat=4&page=2&sort=a

function change_query($queryKey, $queryValue){
    $queryStr = $_SERVER['QUERY_STRING'];
    parse_str($queryStr, $output);
    $output[$queryKey] = $queryValue;
    return http_build_query($output);
}

usage:

<a href="?<?=change_query("sort",'z');?>">sort by z</a>

// http://localhost/arters?sub=Mawson&state=QLD&cat=4&page=2&sort=z

<a href="?<?=change_query("page",'5');?>">Page 5</a>

// http://localhost/arters?sub=Mawson&state=QLD&cat=4&page=5&sort=a