【drawing_settings】
<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'>
window.onload=function(){
var canvas = document.getElementById('canvas');
var c = canvas.getContext('2d');
c.fillStyle = '#cccccc'
c.beginPath();
c.arc(100, 100, 100, 0, 360, false);
c.fill();
}
</script>
</head>
<body>
<canvas id="canvas" width="400" height="200"></canvas>
</body>
</html>
