Are there any built-in PHP functions or methods that provide an all-in-one solution for obtaining the complete Internet address?

To obtain the complete Internet address in PHP, you can use the combination of `$_SERVER['HTTP_HOST']` and `$_SERVER['REQUEST_URI']` variables. The `$_SERVER['HTTP_HOST']` variable contains the host name of the server, while the `$_SERVER['REQUEST_URI']` variable contains the URI of the current request. Concatenating these two variables will give you the complete Internet address.

$completeAddress = "http://".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];
echo $completeAddress;