圆环倒计时我们经常见到，实现的方法也有很多种。但是本文将介绍一种全新的实现方式，使用SVG来实现倒计时功能。

本文主要用到了SVG的stroke-dasharray和stroke-dashoffset特性。下图是倒计时运行效果：

SVG倒计时案例

下面说说相关的实现代码。css实现代码如下：

svg {    transform: rotate(-0.05deg);}circle {    transition: stroke-dasharray .2s;}.time-count-x {    line-height: 1.5;    position: relative;}.time-second {    position: absolute;    top: 50%; left: 0; right: 0;    margin-top: -.75em;    text-align: center;    font-size: 100px;}

相关html代码如下：

<div id="timeCountX" class="time-count-x">    <svg width="440" height="440" viewBox="0 0 440 440" class="center">        <defs>            <linearGradient x1="1" y1="0" x2="0" y2="0" id="gradient1">                <stop offset="0%" stop-color="#e52c5c"></stop>                <stop offset="100%" stop-color="#ab5aea"></stop>            </linearGradient>           <linearGradient x1="1" y1="0" x2="0" y2="0" id="gradient2">                <stop offset="0%" stop-color="#4352f3"></stop>                <stop offset="100%" stop-color="#ab5aea"></stop>            </linearGradient>        </defs>        <g transform="matrix(0,-1,1,0,0,440)">            <circle cx="220" cy="220" r="170" stroke-width="50" stroke="#f0f1f5" fill="none" stroke-dasharray="1069 1069"></circle>            <circle cx="220" cy="220" r="170" stroke-width="50" stroke="url(#gradient1)" fill="none" stroke-dasharray="1069 1069"></circle>            <circle cx="220" cy="220" r="170" stroke-width="50" stroke="url(#gradient2)" fill="none" stroke-dasharray="534.5 1069"></circle>        </g>    </svg>    <span id="timeSecond" class="time-second"></span></div>

最后是相关JavaScript代码：

var eleCircles=document.querySelectorAll("#timeCountX circle");var eleTimeSec=document.getElementById("timeSecond");var perimeter=Math.PI*2*170;var circleInit=function(){    if(eleCircles[1]){        eleCircles[1].setAttribute("stroke-dasharray","1069 1069")    }    if(eleCircles[2]){        eleCircles[2].setAttribute("stroke-dasharray",perimeter/2+" 1069")    }    eleTimeSec.innerHTML=""};var timerTimeCount=null;var fnTimeCount=function(b){    if(timerTimeCount){        return    }    var b=b||10;    var a=function(){        var c=b/10;        if(eleCircles[1]){            eleCircles[1].setAttribute("stroke-dasharray",perimeter*c+" 1069")        }        if(eleCircles[2]&&b<=5){            eleCircles[2].setAttribute("stroke-dasharray",perimeter*c+" 1069")        }        if(eleTimeSec){            eleTimeSec.innerHTML=b        }        b--;        if(b<0){            clearInterval(timerTimeCount);            timerTimeCount=null;            alert("时间到！");            circleInit()        }    };    a();    timerTimeCount=setInterval(a,1000)};fnTimeCount();

整个案例的代码非常少，有喜欢的朋友可以将代码保存到html中，运行一下，体验体验实际效果。

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。