I use tables to contain my html code. Open it on Browser and use "ctrl+a” + copy + paste to my email compose.
But after receiving that email, I found it is not fixed to the phone's screen size.
I think using code behind (such as C#) might solve this problem but is that possible to just use copy + paste to send a suitable size email to smart phone?
<table><tr><td><img style="width:100%;" src="..." alt="..." /></td></tr></table>
<table><tr><td><img style="width:600px;" src="..." alt="..." /></td></tr></table>
Your copy and paste method will work for sending email via Outlook, providing your image links are hosted and not relative.
If you want an email that resizes to the viewport, it is quite an artform and a complex subject to cover. For your simple example though, if you'd like an image that resizes to the email viewport, you can use this:
<table width="100%" border="0" cellpadding="0" cellspacing="0"> <tr> <td> <img style="margin: 0; border: 0; padding: 0; display: block;" src="http://lorempixel.com/400/200/sports/1/" width="100%" alt=""> </td> </tr> </table>