How to create header in mail slim

In Mail Slim, you can create a header by using the header method. Here is an example:

$headers = array(
    'From' => '[email protected]',
    'To' => '[email protected]',
    'Subject' => 'Hello from Mail Slim',
    'MIME-Version' => '1.0',
    'Content-Type' => 'text/plain; charset=UTF-8'
);

$mail = new Mail();
$mail->headers($headers);
$mail->body('Hello, this is a test email.');
$mail->send();

In this example, we create an array of headers and pass it to the headers method of the Mail object. The headers method sets the headers of the email message.

You can also use the header method to set individual headers:

$mail->header('From', '[email protected]');
$mail->header('To', '[email protected]');
$mail->header('Subject', 'Hello from Mail Slim');

Note that the header method overwrites any existing header with the same name. If you want to add a header without overwriting any existing headers, you can use the addHeader method:

$mail->addHeader('From', '[email protected]');
$mail->addHeader('To', '[email protected]');
$mail->addHeader('Subject', 'Hello from Mail Slim');

The addHeader method adds the header to the end of the list of headers, rather than overwriting any existing headers with the same name.