发短信对话框（工作中用到）
<!DOCTYPE HTML>
<html>
<head>
<style type="text/css">
.sendms{float:left;font-size:10px;margin-top:-1em;font-family:Arial;min-width:5%;max-width:80%;}
.sendms .smsing{margin-top:1em;border-radius:0.5em; background:#ccc;padding:0.8em;}
.sendms .sanjiao{margin:0 0 0 1em;}
.sendmsb{float:right;font-size:10px;margin-top:-2em;font-family:Arial;min-width:5%;max-width:80%;clear:left;}
.sendmsb .smsingb{margin-top:1em;border-radius:0.5em;padding:0.8em; background:#669999;color:#fff;}
.sendmsb .sanjiaob{float:right;margin:0 1em 0 0;}
</style>
</head>
<body>
<div width="15" height="15"></canvas></div>
</div>
<div width="15" height="15"></canvas></div>
</div>
</body>
<script type="text/javascript">
var c = document.getElementById('up');
var cxt = c.getContext('2d');
cxt.fillStyle = "#ccc";
cxt.moveTo(0,0);
cxt.lineTo(5,15);
cxt.lineTo(15,0);
cxt.fill();
var c = document.getElementById('upb');
var cxt = c.getContext('2d');
cxt.fillStyle = "#669999";
cxt.moveTo(0,0);
cxt.lineTo(10,15);
cxt.lineTo(15,0);
cxt.fill();
</script>
</html>
