Sending POST data without form

If you don't want your data to be seen by the user, use a PHP session.

Data in a post request is still accessible (and manipulable) by the user.

Checkout this tutorial on PHP Sessions.

Send your data with SESSION rather than post.

session_start();
$_SESSION['foo'] = "bar";

On the page where you recieve the request, if you absolutely need POST data (some weird logic), you can do this somwhere at the beginning:

$_POST['foo'] = $_SESSION['foo'];

The post data will be valid just the same as if it was sent with POST.

Then destroy the session (or just unset the fields if you need the session for other purposes).

It is important to destroy a session or unset the fields, because unlike POST, SESSION will remain valid until you explicitely destroy it or until the end of browser session. If you don't do it, you can observe some strange results. For example: you use sesson for filtering some data. The user switches the filter on and gets filtered data. After a while, he returns to the page and expects the filter to be reset, but it's not: he still sees filtered data.

Simply use: file_get_contents()

// building array of variables
$content = http_build_query(array(
            'username' => 'value',
            'password' => 'value'
            ));
// creating the context change POST to GET if that is relevant 
$context = stream_context_create(array(
            'http' => array(
                'method' => 'POST',
                'content' => $content, )));

$result = file_get_contents('http://www.example.com/page.php', null, $context);
//dumping the reuslt
var_dump($result);

Reference: my answer to a similar question:

You could use AJAX to send a POST request if you don't want forms.

Using jquery $.post method it is pretty simple:

$.post('/foo.php', { key1: 'value1', key2: 'value2' }, function(result) {
    alert('successfully posted key1=value1&key2=value2 to foo.php');
});