How can I add GET variables to end of the current url in php?

Question

I am trying to add a few different GET variables to the url.

I could easily do a header redirect to the current page url and then just add the $_GET['test'] in the url.

My problem is that I have some GET variables that are in the url already. What I want to do is:

• Check if there are any GET variables in the url

  • If there is not, then redirect to the current url with the new GET['test'] variable at the end of the url.

  • If there is, but there is no GET['test'] variable in the url, then keep those other GET values in the url and add the GET['test'] variable to end of the full url string

  • If there is, AND there is a GET['test'] variable in the url, then keep those other GET values in the url and exchange the GET['test'] variable value with the new value.

How can I go about checking for all these conditions?

Solution 1

The simple way to it is:

$params           = array_merge( $_GET, array( 'test' => 'testvalue' ) );
$new_query_string = http_build_query( $params );

This doesn't guarantee that test will be at the end. If for some odd reason you need that, you can just do:

$params = $_GET;
unset( $params['test'] );
$params['test']   = 'testvalue';
$new_query_string = http_build_query( $params );

Note, however, that PHP query string parameter parsing may have some interoperability problems with other applications. In particular, PHP doesn't accept multiple values for any parameter unless it has an array-like name.

Then you can just forward to

( empty( $_SERVER['HTTPS'] ) ? 'http://' : 'https://' ) .
( empty( $_SERVER['HTTP_HOST'] ) ? $defaultHost : $_SERVER['HTTP_HOST'] ) .
$_SERVER['REQUEST_URI'] . '?' . $new_query_string

Solution 2

I created this simple PHP function based on Artefacto's Answer.

function addOrUpdateUrlParam($name, $value)
{
    $params = $_GET;
    unset($params[$name]);
    $params[$name] = $value;
    return basename($_SERVER['PHP_SELF']).'?'.http_build_query($params);
}

• It updates the value if you are changing a existing parameter.
• Adds up if it is a new value

Solution 3

function request_URI() {

    if(!isset($_SERVER['REQUEST_URI'])) {
        $_SERVER['REQUEST_URI'] = $_SERVER['SCRIPT_NAME'];
        if($_SERVER['QUERY_STRING']) {
            $_SERVER['REQUEST_URI'] .= '?' . $_SERVER['QUERY_STRING'];
        }
    }
    return $_SERVER['REQUEST_URI'];
}

$_SERVER['REQUEST_URI'] = request_URI();

Courtesy: http://php.net/manual/en/reserved.variables.server.php example by LOL

This will give you the URL with respect to the root along with GET parameters.

In case you want it with respect to current directory, add the following.

$current_url = explode("/", $_SERVER['REQUEST_URI']);

$current_url = $current_url[end(array_keys($current_url))];

Solution 4

It may just be Joomla reasons, but I get the same value by using:

$currenturl = $_SERVER['REQUEST_URI'] ;

a lot less code.

View more solutions

Comments

[Artefacto]

You know, it's considered good practice to accompany your downvotes with comments, otherwise the answer cannot be improved and the downvote doesn't serve any purpose – the exception being when the answer is clearly inflammatory. This is specially true if you're downvoting an alternative answer to yours; it just seems self-serving otherwise. As to your answer itself, I think you're taking the specifications of the OP too literally, but only he can tell that. Plus, it's really good practice to alter $GET (or $_SERVER).

[Artefacto]

I mean it's not a good practice (the editing windows has closed).

[nathan]

np, up voted now that you've expanded, was going to comment before but pulled away from pc before i could by kids ;)

[MarcGuay]

I believe that this will double-up on the GET vars. If the URL is currently domain.com/page.php?var=1 the final output of the "Then you can just forward to" code is domain.com/page.php?var=1?var=1&test=testvalue.

[Jeffrey Nicholson Carré]

replace REQUEST_URI with PHP_SELF

[Ray S.]

why do you need: unset($params["test"]); isn't it replaced by the statement: $params["test"] = "testvalue";

[M_R_K]

Check My Answer Below. It works like a charm. No GET var double ups. Simple function ;)

[M_R_K]

Check my answer below. I created a simple function based on this answer

[Olivier Van Bulck]

REQUEST_URI and PHP_SELF are both wrong if you have redirects. The best way to do it is by defining the path with: explode('?', $_SERVER['REQUEST_URI'])[0] and add the query after it.