<canvas id="canvas" width="300" height="300">
 <p>抱歉，您的瀏覽器不支持canvas</p>
 </canvas>

 function toCanvas(id ,progress){ canvas進(jìn)度條
 var canvas = document.getElementById(id),
 ctx = canvas.getContext("2d"),
 percent = progress, 最終百分比 circleX = canvas.width / 2, 中心x坐標(biāo) circleY = canvas.height / 2, 中心y坐標(biāo) radius = 100, 圓環(huán)半徑 lineWidth = 5, 圓形線(xiàn)條的寬度 fontSize = 20; 字體大小
 兩端圓點(diǎn)
 function smallcircle1(cx, cy, r) {
 ctx.beginPath(); //ctx.moveTo(cx + r, cy); ctx.lineWidth = 1;
 ctx.fillStyle = '#06a8f3';
 ctx.arc(cx, cy, r,0,Math.PI*2);
 ctx.fill();
 } function smallcircle2(cx, cy, r) {
 ctx.beginPath(); //ctx.moveTo(cx + r, cy); ctx.lineWidth = 1;
 ctx.fillStyle = '#00f8bb';
 ctx.arc(cx, cy, r,0,Math.PI*2);
 ctx.fill();
 } 畫(huà)圓
 function circle(cx, cy, r) {
 ctx.beginPath(); //ctx.moveTo(cx + r, cy); ctx.lineWidth = lineWidth;
 ctx.strokeStyle = '#eee';
 ctx.arc(cx, cy, r, Math.PI*2/3, Math.PI * 1/3);
 ctx.stroke();
 } 畫(huà)弧線(xiàn)
 function sector(cx, cy, r, startAngle, endAngle, anti) {
 ctx.beginPath(); //ctx.moveTo(cx, cy + r); // 從圓形底部開(kāi)始畫(huà) ctx.lineWidth = lineWidth; // 漸變色 - 可自定義
 var linGrad = ctx.createLinearGradient(
 circleX-radius-lineWidth, circleY, circleX+radius+lineWidth, circleY
 );
 linGrad.addColorStop(0.0, '#06a8f3'); //linGrad.addColorStop(0.5, '#9bc4eb'); linGrad.addColorStop(1.0, '#00f8bb');
 ctx.strokeStyle = linGrad; 圓弧兩端的樣式 ctx.lineCap = 'round'; 圓弧 ctx.arc(
 cx, cy, r,
 (Math.PI*2/3), (Math.PI*2/3) + endAngle/100 * (Math.PI*5/3),
 false
 );
 ctx.stroke();
 } 刷新
 function loading() { if (process >= percent) {
 clearInterval(circleLoading);
 } 清除canvas內(nèi)容 ctx.clearRect(0, 0, circleX * 2, circleY * 2); 中間的字 ctx.font = fontSize + 'px April';
 ctx.textAlign = 'center';
 ctx.textBaseline = 'middle';
 ctx.fillStyle = '#999';
 ctx.fillText(parseFloat(process).toFixed(0) + '%', circleX, circleY); 
 
 圓形 circle(circleX, circleY, radius); 
 圓弧 sector(circleX, circleY, radius, Math.PI*2/3, process);
 兩端圓點(diǎn) smallcircle1(150+Math.cos(2*Math.PI/360*120)*100, 150+Math.sin(2*Math.PI/360*120)*100, 5);
 smallcircle2(150+Math.cos(2*Math.PI/360*(120+process*3))*100, 150+Math.sin(2*Math.PI/360*(120+process*3))*100, 5); 控制結(jié)束時(shí)動(dòng)畫(huà)的速度
 if (process / percent > 0.90) {
 process += 0.30;
 } else if (process / percent > 0.80) {
 process += 0.55;
 } else if (process / percent > 0.70) {
 process += 0.75;
 } else {
 process += 1.0;
 }
 } var process = 0.0; 進(jìn)度
 var circleLoading = window.setInterval(function () {
 loading();
 }, 20);
 
 }
第二部分，調(diào)用封裝好的代碼：
 toCanvas('canvas',50);