How to pass/append url parameter to all hrefs (links) on a page?

March 12, 2022

Using javascript, my objective is to query the URL and append parameters to all links on a page. If the link already contains a parameter, the link will append the new parameters:

User access page:https://example.com/?location=brazil
Link on page was: https://link.com/?hello=ok
Link becomes: https://link.com/?hello=ok&location=brazil

If there’s no previous parameter on link, it becomes:
https://link.com/?location=brazil

I tried the following code:

var queryString = new URL(window.location).search;
document.querySelectorAll("[href]").forEach(link => {
    var current = link.href;
    link.href = current + queryString;
});
</script>

But when a link already contains a parameter, it uses ? instead of &
so it becomes:

https://link.com/?hello=ok?location=brazil

How do I solve this problem?

>Solution :

var queryString = new URL(window.location).search;
document.querySelectorAll("[href]").forEach(link => {
    var current = link.href;
    link.href = `${current}${current.includes('?') ? queryString.replace('?', '&') : queryString}`;
});