var n = [];
var e = document.createElement('canvas');
var ctx = e.getContext('2d');
e.width = 2e3;
e.height = 200;
e.style.display = 'inline';
ctx.rect(0, 0, 11, 11);
ctx.rect(3, 3, 6, 6);
n.push('canvas winding:' + (!1 === ctx.isPointInPath(5, 5, 'evenodd') ? 'yes' : 'no'));
ctx.textBaseline = 'alphabetic';
ctx.fillStyle = '#f60';
ctx.fillRect(125, 1, 62, 20);
ctx.fillStyle = '#069';
ctx.font = '11pt Arial';
ctx.fillText('Cwm fjordbank glyphs vext quiz, \ud83d\ude03', 2, 15);
ctx.fillStyle = 'rgba(102, 204, 0, 0.7)';
ctx.font = '18pt Arial';
ctx.fillText('Cwm fjordbank glyphs vext quiz, \ud83d\ude03', 4, 45);
ctx.globalCompositeOperation = 'multiply';
ctx.fillStyle = 'rgb(255,0,255)';
ctx.beginPath();
ctx.arc(52, 50, 50, 0, Math.PI * 2, true);
ctx.closePath();
ctx.fill();
ctx.fillStyle = 'rgb(0,255,255)';
ctx.beginPath();
ctx.arc(100, 50, 50, 0, Math.PI * 2, true);
ctx.closePath();
ctx.fill();
ctx.fillStyle = 'rgb(255,255,0)';
ctx.beginPath();
ctx.arc(75, 100, 50, 0, Math.PI * 2, true);
ctx.closePath();
ctx.fill();
ctx.fillStyle = 'rgb(255,0,255)';
ctx.arc(75, 75, 75, 0, Math.PI * 2, true);
ctx.arc(75, 75, 25, 0, Math.PI * 2, true);
ctx.fill('evenodd');
n.push('canvas fp:' + e.toDataURL());
console.log(n)
标签：fp,canvas,ctx,fillStyle,75,arc,Math,255 From： https://www.cnblogs.com/angdh/p/16871738.html