Ryan Ryan - 17 days ago 4x
PHP Question

Manipulate a url string by adding GET parameters

I want to add GET parameters to URLs that may and may not contain GET parameters without repeating



If I want to add

// will add ?category=action at the end

// will add &category=action at the end

If you notice I'm trying to not repeat the question mark if it's found.

The URL is just a string.

What is a reliable way to append a specific GET parameter?


Basic method

$query = parse_url($url, PHP_URL_QUERY);

// Returns a string if the URL has parameters or NULL if not
if ($query) {
    $url .= '&category=1';
} else {
    $url .= '?category=1';

More advanced

$url = 'http://example.com/search?keyword=test&category=1&tags[]=fun&tags[]=great';

$url_parts = parse_url($url);
parse_str($url_parts['query'], $params);

$params['category'] = 2;     // Overwrite if exists
$params['tags'][] = 'cool';  // Allows multiple values

// Note that this will url_encode all values
$url_parts['query'] = http_build_query($params);

// If you have pecl_http
echo http_build_url($url_parts);

// If not
echo $url_parts['scheme'] . '://' . $url_parts['host'] . $url_parts['path'] . '?' . $url_parts['query'];

You should put this in a function at least, if not a class.