Javascript 使用DOM绘制钟摆
这是代码,我画了两个圆圈和两条线,另外一条线与第二条线平行Javascript 使用DOM绘制钟摆,javascript,html,css,dom,canvas,Javascript,Html,Css,Dom,Canvas,这是代码,我画了两个圆圈和两条线,另外一条线与第二条线平行 var canvas=document.getElementById(“面板”); var draw=canvas.getContext(“2d”); draw.beginPath(); 绘制弧(画布宽度/2100,10,2*Math.PI,假); draw.fillSytle=“黑色”; draw.fill(); 绘制弧(画布宽度/2200,10,2*Math.PI,假); draw.fillSytle=“黑色”; draw.fil
var canvas=document.getElementById(“面板”);
var draw=canvas.getContext(“2d”);
draw.beginPath();
绘制弧(画布宽度/2100,10,2*Math.PI,假);
draw.fillSytle=“黑色”;
draw.fill();
绘制弧(画布宽度/2200,10,2*Math.PI,假);
draw.fillSytle=“黑色”;
draw.fill();
draw.moveTo(画布宽度/2,0);
绘制线条(画布宽度/2100);
draw.moveTo(画布宽度/2100);
绘制线条(画布宽度/2200);
draw.stroke();
检查下面的代码片段。你只需要画两张单独的表格
var canvas=document.getElementById(“面板”);
var draw=canvas.getContext(“2d”);
draw.beginPath();
绘制弧(canvas.width/2-50200,10,2*Math.PI,假);
draw.fillSytle=“黑色”;
draw.fill();
draw.moveTo(canvas.width/2-50,0);
draw.lineTo(canvas.width/2-50200);
draw.stroke();
var draww=canvas.getContext(“2d”);
draww.beginPath();
绘制弧(canvas.width/2+50200,10,2*数学圆周率,假);
draww.fillSytle=“黑色”;
draww.fill();
draww.moveTo(画布宽度/2+50,0);
图纸线条(画布宽度/2+50200);
draww.stroke()代码>
不需要draww=canvas.getContext(“2d”)
getContext()
将返回与以前相同的对象。所需要的只是开始一条新的道路。我画的每一件东西都必须这样做吗?在javaScript中绘制图形的更好方法是什么?您可以始终使用循环
<html>
<head>
<body>
<canvas id="Panel" height=500 width=500 style ="border: 1px dotted green">
</canvas>
</body>
<script>
var canvas = document.getElementById("Panel");
var draw = canvas.getContext("2d");
draw.beginPath();
draw.arc(canvas.width/2,100,10,2*Math.PI,false);
draw.fillSytle="black";
draw.fill();
draw.arc(canvas.width/2,200,10,2*Math.PI,false);
draw.fillSytle="black";
draw.fill();
draw.moveTo(canvas.width/2,0);
draw.lineTo(canvas.width/2,100);
draw.moveTo(canvas.width/2,100);
draw.lineTo(canvas.width/2,200);
draw.stroke();
</script>
</head>
</html>