效果如下：
代碼如下：
<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <meta name="viewport" content="maximum-scale=1.0,minimum-scale=1.0,user-scalable=0,width=device-width,initial-scale=1.0"/> <meta name="format-detection" content="telephone=no,email=no,date=no,address=no"> <title>canvas繪制環形進度條</title> <style type="text/css"> .chartbox{width: 100px;margin: 100px auto;} .myChart{width:100px;height: 100px;} </style></head><body> <div class="chartbox"> <canvas class="myChart" id="myChart" width="100%" height="100%" data-total="100" data-curr="29.45"></canvas> </div> <script typet="text/javascript" src="http://libs.baidu.com/jquery/1.9.1/jquery.min.js"></script> <script type="text/javascript"> (function($, window, undefined) { $.fn.ringChart = function(options) { var defaults = { }; var settings = $.extend({}, defaults, options); var canvas = $(this).get(0); var total = $(this).attr("data-total"); var curr = $(this).attr("data-curr"); var constrast = parseFloat(curr/total).toFixed(2); //比例 var context = null; if ( !canvas.getContext) { return; } // 定義開始點的大小 var startArc = Math.PI*1.5; // 根據占的比例畫圓弧 var endArc = (Math.PI * 2) * constrast; context = canvas.getContext("2d"); // 圓心文字 context.font="28px Arial"; context.fillStyle = '#ff801a'; context.textBaseline = 'middle'; var text=(Number(curr/total)*100).toFixed(0)+"%"; var tw=context.measureText(text).width; context.fillText(text,50-tw/2,50); // 繪制背景圓 context.save(); context.beginPath(); context.strokeStyle = "#e7e7e7"; context.lineWidth = "4"; context.arc(50, 50, 44, 0, Math.PI * 2, false); context.closePath(); context.stroke(); context.restore(); // 若為百分零則不必再繪制比例圓 if ( curr / total == 0) { return; } // 繪制比例圓 context.save(); context.beginPath(); context.strokeStyle = "#ff801a"; context.lineWidth = "4"; context.arc(50, 50, 44, startArc, (curr % total == 0 ? startArc : (endArc+startArc)), false); context.stroke(); context.restore(); } })($, window); $("#myChart").ringChart(); </script></body></html>以上就是本文的全部內容，希望本文的內容對大家的學習或者工作能帶來一定的幫助，同時也希望多多支持武林網！
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