JS+H5 Canvas实现时钟效果

时间:2018-07-20
这篇文章主要为大家详细介绍了JS+H5 Canvas实现时钟效果,利用JavaScript和Canvas实现简单时钟效果,具有一定的参考价值,感兴趣的小伙伴们可以参考一下

用JavaScript+Canvas来实现最简单的时钟效果,供大家参考,具体内容如下

效果图:

先看html代码:

<html>
 <head>
 <meta charset="UTF-8">
 <title></title>
 <script type="text/javascript" src="js/demo3.js" ></script>
 </head>
  <body>
 <canvas id = "canvas"></canvas>
  </body>
</html>

JavaScript代码:

var canvas,context;
function draw(){//定义划时钟的方法
 var data = new Date();
 var hHoure = data.getHours();
 var mMin = data.getMinutes();
 var sSec = data.getSeconds();
 var hValue = (hHoure*30+mMin/2-90)*Math.PI/180; 
 var mValue = (mMin*6-90)*Math.PI/180;
 var sValue = (sSec*6 -90)*Math.PI/180;
 var x = 200,y = 200,r = 150;
 
 context.clearRect(0,0,canvas.width,canvas.height);
 context.moveTo(x,y);
 context.arc(x,y,r,0,6*Math.PI/180,false);
 //
 context.beginPath();
 context.lineWidth = 1;
 for(var i = 0;i<60;i++){
 context.moveTo(x,y);
 context.arc(x,y,r,6*i*Math.PI/180,6*(i+1)*Math.PI/180,false);
 }
 context.closePath();
 context.stroke();
 //
 context.beginPath();
 context.fillStyle = "white";
 context.moveTo(x,y);
 context.arc(x,y,r/1.1,-0,2*Math.PI,false);
 context.closePath();
 context.fill();
 // 
 context.beginPath();
 context.lineWidth = 3;
 for(var i = 0;i<12;i++){
 context.moveTo(x,y);
 context.arc(x,y,r,30*i*Math.PI/180,30*(i+1)*Math.PI,false);
 }
 context.closePath();
 context.stroke();
 //
 context.beginPath();
 context.fillStyle = "white";
 context.moveTo(x,y);
 context.arc(x,y,r/1.12,0,2*Math.PI,false);
 context.closePath();
 context.fill();
 
 context.beginPath();
 context.fillStyle = "black";
 context.moveTo(x,y);
 context.arc(x,y,r/30,0,2*Math.PI,false);
 context.fill(); 
 //
 context.beginPath();
 context.lineWidth = 5;
 context.moveTo(x,y);
 context.arc(x,y,r/2.5,hValue,hValue,false);
 context.stroke();
 //
 context.beginPath();
 context.lineWidth = 3;
 context.moveTo(x,y);
 context.arc(x,y,r/2,mValue,mValue,false);
 context.stroke(); 
 //
 context.beginPath();
 context.lineWidth = 2;
 context.moveTo(x,y);
 context.arc(x,y,r/1.6,sValue,sValue,false);
 context.stroke();
}
window.onload = function(){
 canvas = document.getElementById('canvas');
 context = canvas.getContext('2d');
 canvas.height = 500;
 canvas.width = 500;
 setInterval(draw,1000); 
 draw(); 
}

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。