As I have previously stated, I do my best to use mailto as infrequently as possible because of all the associated problems. Occasionally, clients will request this functionality regardless of the consequences. Today I had to post a mailto link in Flash for which I wrote this tutorial. To expand on that link, the client also wanted us to populate the email with a subject and body content.
Using HTML, I have populated the subject of mailto links many times but I had never attempted to populate the body. It turns out it works just the same as subject and couldn’t be any easier. I thought this may be the case, so I tried it before I looked around and it worked. It is not too often that this method of coding works for me, but I got lucky for once.
Here is the code if you don’t know what I am talking about:
<a href="mailto:firstname.lastname@example.org?subject=This is the Subject&body=This is the content of the email.">Email Link</a>
Quoted from: stemkoski.com