How to send mail with binary word in mail subject using PHP

Question

I am going to send mail through PHP website. Client may custom the mail subject and I will get the post data in UTF-8. But When I send out a html mail using the php mail(), I found the the mail subject cannot show properly while the mail body does.

How to send chinese word in PHP mail function?

Thanks.

Answer 1

You need to encode the subject according to how encoded-word is specified (see RFC 2047):

encoded-word = "=?" charset "?" encoding "?" encoded-text "?="

You can either use

• the Base64 encoding (base64_encode):

  'Subject: =?UTF-8?B?'.base64_encode($subject).'?='
  

  or

• the quoted-printable encoding (see RFC 2045, imap_8bit):

  'Subject: =?UTF-8?Q?'.imap_8bit($subject).'?='
  

Answer 2

It's quite involved to send non-ASCII in mail header. Check out PHPMailer,

http://sourceforge.net/projects/phpmailer/

If it doesn't work for you, look at encoderHeader() to see how it's done.