<html>
<body>
<canvas id="myCanvas" width="300" height="150" style="border:1px solid #d3d3d3;">
您的浏览器不支持 HTML5 canvas 标签。</canvas>
<script>
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
ctx.beginPath();
ctx.moveTo(20,20); // Create a starting point
ctx.lineTo(100,20); // Create a horizontal line
ctx.arcTo(150,20,150,70,50); // Create an arc
ctx.lineTo(150,120); // Continue with vertical line
ctx.stroke(); // Draw it
</script>
</body>
</html>