There is no way to write a relative URI that preserves the existing query string while adding additional parameters to it.
You have to:
topic.php?id=14&like=like
function currentUrl() {
$protocol = strpos(strtolower($_SERVER['SERVER_PROTOCOL']),'https') === FALSE ? 'http' : 'https';
$host = $_SERVER['HTTP_HOST'];
$script = $_SERVER['SCRIPT_NAME'];
$params = $_SERVER['QUERY_STRING'];
return $protocol . '://' . $host . $script . '?' . $params;
}
Then add your value with something like;
echo currentUrl().'&value=myVal';
I know I'm late to the game, but you can just do ?id=14&like=like by using http build query as follows:
http_build_query(array_merge($_GET, array("like"=>"like")))
Whatever GET parameters you had will still be there and if like was a parameter before it will be overwritten, otherwise it will be included at the end.
In case you want to add the URL parameter in JavaScript, see this answer. As suggested there, you can use the URLSeachParams API in modern browsers as follows:
<script>
function addUrlParameter(name, value) {
var searchParams = new URLSearchParams(window.location.search)
searchParams.set(name, value)
window.location.search = searchParams.toString()
}
</script>
<body>
...
<a onclick="addUrlParameter('like', 'like')">Like this page</a>
...
</body>
If you wish to use "like" as a parameter your link needs to be:
<a href="/topic.php?like=like">Like</a>
More likely though is that you want:
<a href="/topic.php?id=14&like=like">Like</a>
It is not elegant but possible to do it as one-liner <a> element
<a href onclick="event.preventDefault(); location+='&like=like'">Like</a>Maybe you can write a function as follows:
var addParams = function(key, val, url) {
var arr = url.split('?');
if(arr.length == 1) {
return url + '?' + key + '=' + val;
}
else if(arr.length == 2) {
var params = arr[1].split('&');
var p = {};
var a = [];
var strarr = [];
$.each(params, function(index, element) {
a = element.split('=');
p[a[0]] = a[1];
})
p[key] = val;
for(var o in p) {
strarr.push(o + '=' + p[o]);
}
var str = strarr.join('&');
return(arr[0] + '?' + str);
}
}
Source: Stackoverflow.com