better way to replace query string value in a given url

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";

Basically, I need to create a function, which replaces each thing in the URL, for example:

<a href="<?=$url;?>?sort=a">Sort by A-Z</a>
<a href="<?=$url;?>?sort=z">Sort by Z-A</a>

Or, for another example:

<a href="<?=$url;?>?cat=1">Category 1</a>
<a href="<?=$url;?>?cat=2">Category 2</a>

Or, another example:

<a href="<?=$url;?>?page=1">1</a>
<a href="<?=$url;?>?page=2">2</a>
<a href="<?=$url;?>?page=3">3</a>
<a href="<?=$url;?>?page=4">4</a>

So basically, we need a function which will replace the specific $_GET from the URL so that we don't get a duplicate, such as: ?page=2&page=3

Having said that, it needs to be smart, so it knows if the beginning of the parameter is a ? or an &

We also need it to be smart so that we can have the URL like so:

<a href="<?=$url;?>page=3">3</a> (without the ? - so it will detect automatically wether to use an `&` or a `?`

I don't mind making different variables for each preg_replace for the certain $_GET parameters, but I am looking for the best way to开发者_C百科 do this.

Thank you.

How about something like this?

function merge_querystring($url = null,$query = null,$recursive = false)
{
  // $url = 'http://www.google.com.au?q=apple&type=keyword';
  // $query = '?q=banana';
  // if there's a URL missing or no query string, return
  if($url == null)
    return false;
  if($query == null)
    return $url;
  // split the url into it's components
  $url_components = parse_url($url);
  // if we have the query string but no query on the original url
  // just return the URL + query string
  if(empty($url_components['query']))
    return $url.'?'.ltrim($query,'?');
  // turn the url's query string into an array
  parse_str($url_components['query'],$original_query_string);
  // turn the query string into an array
  parse_str(parse_url($query,PHP_URL_QUERY),$merged_query_string);
  // merge the query string
  if($recursive == true)
    $merged_result = array_merge_recursive($original_query_string,$merged_query_string);
  else
    $merged_result = array_merge($original_query_string,$merged_query_string);
  // Find the original query string in the URL and replace it with the new one
  return str_replace($url_components['query'],http_build_query($merged_result),$url);
}

usage...

<a href="<?=merge_querystring($url,'?page=1');?>">Page 1</a>
<a href="<?=merge_querystring($url,'?page=2');?>">Page 2</a>

Well, I had same problem, found this question, and, in the end, prefered my own method. Maybe it has flaws, then please tell me what are they. My solution is:

$query=$_GET;
$query['YOUR_NAME']=$YOUR_VAL;
$url=$_SERVER['PHP_SELF']. '?' .  http_build_query($query);

Hope it helps.

<?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 ;)

function replaceQueryParams($url, $params)
{
    $query = parse_url($url, PHP_URL_QUERY);
    parse_str($query, $oldParams);

    if (empty($oldParams)) {
        return rtrim($url, '?') . '?' . http_build_query($params);
    }

    $params = array_merge($oldParams, $params);

    return preg_replace('#\?.*#', '?' . http_build_query($params), $url);
}

$url examples:

• http://example.com
• http://example.com/
• http://example.com/page
• http://example.com/page?
• http://example.com/page?foo=bar
• http://example.com/page?foo2=bar2
• http://example.com/page?foo=bar&foo2=bar2

$params example:

[
   'foo' => 'not-bar',
]

Note: it doesn't understand URLs with anchors (hashes) like http://example.com/page?foo=bar#section1

If I'm reading this correctly, and I may not be. You know which GET you are replacing in a url string? This may be sloppy but...

$url_pieces = explode( '?', $url );
$var_string = $url_pieces[1].'&';
$new_url = $url_pieces[0].preg_replace( '/varName\=value/', 'newVarName=newValue', $var_string );

That's my take, Good luck.

I don't know if this is what you're trying to accomplish but here it goes anyway:

<?php
    function mergeMe($url, $assign) {
        list($var,$val) = explode("=",$assign);
        //there's no var defined
        if(!strpos($url,"?")) {
            $res = "$url?$assign";
        } else {
            list($base,$vars) = explode("?",$url);
            //if the vars dont include the one given
            if(!strpos($vars,$var)) {
                $res = "$url&$assign";
            } else {
                $res = preg_replace("/$var=[a-zA-Z0-9_]*(&|$)/",$assign."&",$url);
                $res = preg_replace("/&$/","",$res); //remove possible & at the end
            }
        }
        //just to show the difference, should be "return $res;" instead
        return "$url <strong>($assign)</strong><br>$res<hr>";
    }

    //example
    $url1 = "http://example.com";
    $url2 = "http://example.com?sort=a";
    $url3 = "http://example.com?sort=a&page=0";
    $url4 = "http://example.com?sort=a&page=0&more=no";

    echo mergeMe($url1,"page=4");
    echo mergeMe($url2,"page=4");
    echo mergeMe($url3,"page=4");
    echo mergeMe($url4,"page=4");
?>

improve Scuzzy 2013 function last pieces for clean url query string.

// merge the query string
// array_filter removes empty query array
    if ($recursive == true) {
        $merged_result = array_filter(array_merge_recursive($original_query_string, $merged_query_string));
    } else {
        $merged_result = array_filter(array_merge($original_query_string, $merged_query_string));
    }

    // Find the original query string in the URL and replace it with the new one
    $new_url = str_replace($url_components['query'], http_build_query($merged_result), $url);

    // If the last query string removed then remove ? from url 
    if(substr($new_url, -1) == '?') {
       return rtrim($new_url,'?');
    }
    return $new_url;

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

/**
* URL Parameters : Replace query string value in a url
*
* @version 2023.02.21 Jwu
*
* @param string $queryKey Variable name 
* @param string|null $queryValue Property value
* 
* @return string
*/
function changeQueryString($queryKey, $queryValue){
    $queryStr = $_SERVER['QUERY_STRING'];
    parse_str($queryStr, $output);
    if($queryValue == null){
        unset($output[$queryKey]);
    }else{
        $output[$queryKey] = $queryValue;
    }
    $actualLink = 'http' . (isset($_SERVER['HTTPS']) ? 's' : '') . '://' . $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF'];
    return $actualLink . '?' . http_build_query($output);
}

usage:

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

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

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

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

My short and readable way:

function replaceGetParameters(string $url, array $newGetParameters): string {
    $url_parts = parse_url($url);
    $query = [];
    if (isset($url_parts['query'])) {
      parse_str($url_parts['query'], $query);
    }
    $query = array_merge($query, $newGetParameters);
    $url_parts['query'] = http_build_query($query);
    return $url_parts['scheme'] . '://' . $url_parts['host'] . $url_parts['path'] . '?' . $url_parts['query'];
  }