What is the correct way to use http_build_query with "post" data in PHP?

When using http_build_query with "post" data in PHP, you need to pass an array of data as the second parameter to the function. This array should contain key-value pairs of the data you want to send as POST parameters.

// Example of using http_build_query with "post" data
$data = array(
    'username' => 'john_doe',
    'password' => 'password123'
);

$postData = http_build_query($data);

// Now you can use $postData in your HTTP request