我试图使用画布绘制一个星,但代码没有运行.我想了解:测量Y和X坐标的步骤是什么？怎么找到他们？绘制任何形状？
<html>
<head>
<meta charset = "utf-8">
<title>Drawing Lines</title>
</head>
<body>
<canvas id = "drawLines" width = "400" height = "200"
style = "border: 1px solid Black;">
</canvas>
<script>
var canvas = document.getElementById("drawLines");
var context = canvas.getContext("2d")
canvas.beginPath();
canvas.moveTo(50,50);
canvas.lineTo(120,150);
canvas.lineTo(0,180);
canvas.lineTo(120,210);
canvas.lineTo(50,310);
canvas.lineTo(160,250);
canvas.lineTo(190,370);
canvas.lineTo(220,250);
canvas.lineTo(330,310);
canvas.lineTo(260,210);
canvas.lineTo(380,180);
canvas.closePath();
canvas.stroke();
</script>
</body>
</html>