<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta content="width=device-width, initial-scale=1.0"> <title>Document</title> <script> window.onload=function(){ var canvas=document.getElementById('canvas'); var cx=canvas.getContext("2d"); cx.fillStyle='pink'; cx.strokeStyle='pink'; for(var i=0;i<10;i++){ var g=cx.createLinearGradient(0,0,290,290); g.addColorStop(0,'rgba(255,0,0,1)'); g.addColorStop(0.1,'rgba(255,0,0,0.5)'); g.addColorStop(0.2,'rgba(255,165,0,0.4)'); g.addColorStop(0.4,'rgba(205,255,0,0.5)'); g.addColorStop(0.6,'rgba(230,145,0,0.5)'); g.addColorStop(0.8,'rgba(0,127,255,0.5)'); g.addColorStop(0.9,'rgba(100,200,205,0.9)'); g.addColorStop(1,'rgba(0,255,255,0.5)');; cx.fillStyle=g; cx.beginPath(); cx.arc(i*25,i*25,i*10,0,Math.PI*2,true); cx.closePath(); cx.fill(); } } </script> </head> <body> <canvas></canvas> </body> </html>
效果图如下：
