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<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>慕课网Wiki</title> <style> #imooc{ border:1px solid #ccc; } </style> </head> <body> <canvas id="imooc">您的浏览器不支持 HTML5 canvas 标签</canvas> <script> const canvas = document.getElementById('imooc'); canvas.width=300 canvas.height=300 const ctx = canvas.getContext('2d'); ctx.strokeStyle="#456795"; ctx.lineWidth=8; ctx.beginPath(); ctx.moveTo(40,40); ctx.quadraticCurveTo(260,150, 40,260); //调用了直接绘制椭圆的函数 ctx.stroke(); //绘制起点 ctx.beginPath(); ctx.arc(40,40,8,0,2*Math.PI) ctx.fillStyle= "#888" ctx.fill() //绘制控制点 ctx.beginPath(); ctx.arc(260,150,8,0,2*Math.PI) ctx.fillStyle= "#888" ctx.fill() //绘制终点 ctx.beginPath(); ctx.arc(40,260,8,0,2*Math.PI) ctx.fillStyle= "#888" ctx.fill() </script> </body> </html>
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