How can PHP developers ensure that email attachments are properly encoded and decoded for safe transmission?

To ensure that email attachments are properly encoded and decoded for safe transmission, PHP developers can use the base64_encode() function to encode the attachment data before sending it in an email, and then use base64_decode() function to decode the attachment data when receiving the email.

// Encode attachment data before sending email
$attachment_data = file_get_contents('path/to/attachment.pdf');
$encoded_attachment = base64_encode($attachment_data);

// Decode attachment data when receiving email
$decoded_attachment = base64_decode($encoded_attachment);