Manipulate a url string by adding GET parameters

Question

I want to add GET parameters to URLs that may and may not contain GET parameters without repeating ? or &.

Example:

If I want t

Answer 1

Use strpos to detect a ?. Since ? can only appear in the URL at the beginning of a query string, you know if its there get params already exist and you need to add params using &

function addGetParamToUrl(&$url, $varName, $value)
{
    // is there already an ?
    if (strpos($url, "?"))
    {
        $url .= "&" . $varName . "=" . $value; 
    }
    else
    {
        $url .= "?" . $varName . "=" . $value;
    }
}

Answer 2

Try this function to add URL parameters.

Then you can disable the link when parameter is set so there is no url parameter duplicate.

<?php
  function addQueryString($a)
                {
             if (empty($_SERVER['QUERY_STRING']))
               return '?' . $a;
             else if (!empty($_SERVER['QUERY_STRING']))
              return '?' . $_SERVER['QUERY_STRING'] . '&' . $a;
                }
?>

 <a href="<?php echo addQueryString('lang=en'); ?>">test</a>
 <a href="<?php echo addQueryString('category=5'); ?>">sat</a>

Answer 3

In case you are using WordPress you can simply use

    add_query_args(['sort' => 'asc'], 'http:/example.com/?search=news')

Docs https://developer.wordpress.org/reference/functions/add_query_arg/