如何使特殊字符与mailto：link（PHP）兼容？

Question

I'm trying to put html into a mailto link (<a href='mailto:...) and using htmlescapechars() but this doesn't seem to be what I need.

<a href='mailto:?subject=<?echo $subject_e=htmlspecialchars($subject, ENT_QUOTES)?>&body=<?=$subject_e?>%20via%20https&#58;&#47;&#47;mySite.com&#47;<?=htmlspecialchars($subjectLink, ENT_QUOTES)?>%20'>some text</a>

Can anyone explain under what conditions Example #1 in the htmlspecialchars() part of PHP's documentation works?

$new = htmlspecialchars("<a href='test'>Test</a>", ENT_QUOTES);
echo $new; // &lt;a href=&#039;test&#039;&gt;Test&lt;/a&gt;

Running this function on my own server or on http://writecodeonline.com/php/ doesn't seem to convert the special characters.

So it doesn't appear to be a PHP version issue. Including the encoding parameter also had no effect. Wtf?

Answer 1

So after looking elsewhere on SO, I realized instead of htmlspecialchars() I just needed rawurlencode().