Phpmailer配置

I have installed phpmailer for cpanel using composer successfully.

The location of PHPMailer is at

root\vendor\phpmailer\phpmailer

now I want to use PHPmailer in one of my files at

root\public_html

What changes do I have to make to the following lines ?

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception; 
require 'vendor/autoload.php';

the code is not working with the above configuration.The rest of code is same as that given in the documentation (with correct values filled)

If your current working directory is root\public_html (I'm assuming you're on Windows since you're using \ in paths) and you want to load the composer autoloader from there when it's stored in root\vendor\autoload.php, you should load it from a relative path like this:

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception; 
require '../vendor/autoload.php';

Note that the namespace aliases (the use lines) do not change.

While this should work, a better solution is to add your app's root folder (in this example root\, wherever that is as an absolute path) to your php.ini's include_path setting, and that way the original vendor/autoload.php will work.