How to detect "?" in Site links for redirection?

Question

I am using a Function for redirection of external links in my website

How This Function works:- it will detect all nearbuy.com links and Apply a redirection Rule and then redirected.

For Example:- nearbuy.com is a domain So this function add prefix before nearbuy.com external url i.e http://tracking.nearbuy.com/aff_c?offer_id=9&aff_id=479&url=

Then http://www.nearbuy.com and url parameter to make it work.

What i want to do:-

1) If nearbuy.com link already has "?" then it will use "&"

2) If nearbuy.com link don't have "?" then it will use "?"

What is problem:-

I am using below Method but its not detecting "?" in links and add "?" again in end of links while redirection which is problem

Here is Code:-

if(stripos($url, "nearbuy.com")) {
    $url_args = parse_url($url);
    $url_params = "?utm_source=nap&utm_medium=cps&utm_campaign={affiliate_id}";
        if(!empty($durl["query"])) {    
            $url_params = "&utm_source=nap&utm_medium=cps&utm_campaign={affiliate_id}";
        }
    $redirect_url = "http://tracking.nearbuy.com/aff_c?offer_id=9&aff_id=479&url=" . urlencode($url . $url_params);
        goto redirect_to_uri;
    break;
}

Answer 1

You could use parse_url and do something like:

$yourQueryParams = [
    'offer_id' => 9,
    'aff_id' => 479,
];

$url .= (parse_url($url, PHP_URL_QUERY) ? '&' : '?') . http_build_query($yourQueryParams);

// redirect with your query params
header("Location: $url");
die();