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。
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();
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以上就是svg怎样开始实现多彩圆环倒计时的详细内容。