代码：
<!DOCTYPE html> <html> <head> <meta charset="utf-8"/> <title>时钟</title> <style> *{margin: 0; padding: 0;} div.dd{ margin: 0 auto; width: 400px; padding-top: 100px; } </style> </head> <body> <div> <canvas>你的浏览器不支持canvas</canvas> </div> <script type="text/javascript"> (function(doc){ var can = doc.getElementById("clock"); var con = can.getContext("2d");//创建一个2d上下文 con.translate(200, 200);//重新确定坐标原点（确定圆心位置） //外圆 con.beginPath(); con.fillStyle = '#fff'; con.arc(0, 0, 200, 0, Math.PI*2, false); con.fill(); //内圆 con.beginPath(); con.fillStyle = '#aaa'; con.arc(0, 0, 195, 0, Math.PI*2, false); con.fill(); //绘制刻度 con.beginPath(); con.font = "bold 20px sans-serif"; con.textAlign = "center"; con.textBaseline = "middle" con.fillStyle = '#000000'; con.fillText("12", 0, -170); con.fillText("3",170,0); con.fillText("6",0,170); con.fillText("9",-170,0); con.fillText("1",84,-147.224); con.fillText("2",147.224,-84); con.fillText("4",147.224,84); con.fillText("5",84,147.224); con.fillText("7",-84,147.224); con.fillText("8",-147.224,84); con.fillText("10",-147.224,-84); con.fillText("11",-84,-147.224); //获取当前时间 var d = new Date(), time ={}; time.H = d.getHours()%12; time.M = d.getMinutes(); time.S = d.getSeconds(); function getTime(){ time.S++; if(time.S > 59){ time.S = 0; time.M++; if(time.M > 60){ time.M = 0; time.H++; if(time.H > 11){ time.H = 0; } } } canvasTimeLine(); } //将角度转为弧度 function numToDeg(num){ return ((num*6 - 90)*0.0174444444444444); } //确定刻度位置 function computePositionByLenDeg(len, deg){ return { x: len*Math.cos(deg), y: len*Math.sin(deg) } } //绘制刻度 function canvasLineMintus(){ for(var i = 0;i<60; i++){ var rec = 180; con.beginPath(); con.lineWidth = 4; if(i%5 != 0){ con.lineWidth = 1; rec = 184 } var beinDeg = numToDeg(i), beginPot = computePositionByLenDeg(rec, beinDeg), endPot = computePositionByLenDeg(190, beinDeg); con.moveTo(beginPot.x, beginPot.y); con.lineTo(endPot.x, endPot.y); con.stroke(); } } function canvasTimeLine(){ var sDeg = numToDeg(time.S), mDeg = numToDeg(time.M), hDeg = numToDeg(time.H*5 + Math.floor(time.M/12)), sPot = computePositionByLenDeg(150, sDeg), mPot = computePositionByLenDeg(135, mDeg), hPot = computePositionByLenDeg(110, hDeg); //时钟表面 con.beginPath(); con.fillStyle = '#ddd'; con.arc(0, 0, 156, 0, Math.PI*2, false); con.fill(); //时针 con.beginPath(); con.moveTo(0, 0); con.lineTo(hPot.x, hPot.y); con.lineWidth = 6; con.strokeStyle = "#333"; con.stroke(); //分针 con.beginPath(); con.moveTo(0, 0); con.lineTo(mPot.x, mPot.y); con.lineWidth = 4; con.strokeStyle = "#333"; con.stroke(); //秒针 con.beginPath(); con.moveTo(0, 0); con.lineTo(sPot.x, sPot.y); con.lineWidth = 2; con.strokeStyle = "#ff0000"; con.stroke(); //针心 con.beginPath(); con.fillStyle = '#aaaaaa'; con.arc(0, 0, 8, 0, Math.PI*2, false); con.fill(); con.beginPath(); con.fillStyle = '#f00'; con.arc(0, 0, 4, 0, Math.PI*2, false); con.fill(); } canvasLineMintus(); getTime(); setInterval(getTime, 1000); })(document); </script> </body> </html>