Special characters in UTF8 mailto: subject= link and Outlook

Question

I'm in the last stages of re-coding a site that formally used iso-8859-1 character encoding, but now is UTF-8 throughout.

The problem is that the subject section of the mailto href link is not working with Outlook, when special characters are used. I get the usual garbled character representations, indicative of an obvious character encoding issue when the link is clicked and the new mail window pops up in outlook.

I've tried rawurlencode() to fix ths issue, but this doesn't seem to work with Outlook...

<a href="mailto:[email protected]?subject=<?=rawurlencode($subj);?>">send email</a>

So then thought, Outlook must insist on a different encoding, and tried utf-8 decoding the subject string first...

<a href="mailto:[email protected]?subject=<?=rawurlencode(utf8_decode($subj));?>">send email</a>

Bingo! Works great Outlook. But now fails in everything else :(

I can't find a solution that works accross all mail clients.

It worked fine across all mail clients when the whole page was displayed in iso-8859-1. But not when the page content is utf-8.

Unfortunately the client wants to retain this direct email link, despite having a functioning mail form directly beneath it!

Is there a happy solution to this?

Answer 1

If you use utf-8 try this:

<?php $subject = "=?UTF-8?B?" . base64_encode($subject) . "?="; ?>

Answer 2

The reason the subject line is sometimes garbled is because when you specify an encoding, it doesn't apply to the email header. Your subject line is in the email header. Here's a function to apply UTF8 encoding on the subject line:

function EncodeSubject($_subject)
{
    $encodedSubject = str_replace(""", '"', $_subject);
    $encodedSubject = preg_replace('/[^x09\x20-\x3C\x3E-\x7E]/e', 'sprintf("=%02X", ord("$0"));', $encodedSubject);
    $encodedSubject = str_replace(' ', '_', $encodedSubject);
    return ="?utf-8?q" . $encodedSubject . "?=";
}