本篇文章给大家带来的内容是关于使用css3和js实现一个钟表代码过程，有一定的参考价值，有需要的朋友可以参考一下，希望对你有所帮助。
有一天看到css3旋转这个属性,突发奇想的写了一个钟表(没做浏览器兼容),来一起看看是怎么写的吧!
先给个成品图,最终结果是个样子的(动态的).
首先,思考了一下页面的布局,大致需要4层p,最底层是一个表盘的背景图,然后其余3层分别是时针,分针,秒针的图层.
html代码如下
<div class="dial"></div><div class="bigdiv bigdiv1" id="secondHand"> <div class="secondHand"></div></div><div class="bigdiv bigdiv2" id="minuteHand"> <div class="minuteHand"></div></div><div class="bigdiv bigdiv3" id="hourHand"> <div class="center"></div> <div class="hourHand"></div></div>
变量名是随便起的,不要介意; class=center的这个p是表中心那个小黑点.
时针是60*60*60s转一圈, 分针是60*60s转一圈, 秒针是60s转一圈, 所以css代码如下 ↓
.dial{ width:600px; height:600px; margin:0 auto; position: absolute; border-radius: 50%; overflow: hidden; background-color: rgba(153,50,204,0.2); background-image: url(img/表盘.jpg); background-size: 100% 100%;}.bigdiv{ width:600px; height:600px; margin:0 auto; position: absolute; border-radius: 50%; overflow: hidden;}.bigdiv>div{ position: absolute; left:298px; border-radius: 100px;}.bigdiv1{ animation: moves 60s steps(60) infinite;}.bigdiv1 .secondHand{ width:4px; height:250px; background-color: red; top:50px; left:298px;}.bigdiv2{ animation: moves 3600s steps(3600) infinite;}.bigdiv2 .minuteHand{ width:6px; height:180px; background-color: green; top:120px; left:297px;}.bigdiv3{ animation: moves 216000s steps(216000) infinite;}.bigdiv3 .hourHand{ width:8px; height:160px; background-color: orange; top:140px; left:296px; border-radius: 100px;}.bigdiv .center{ top:290px; left:290px; width:20px; height:20px; background-color: black; z-index: 2;}@keyframes moves{ from{ transform: rotateZ(0deg); } to{ transform: rotateZ(360deg); }}这一步做完后效果图是这个样子的:
然后用js计算当前时间,
var date = new Date();var hours = date.getHours();var minutes = date.getMinutes();var seconds = date.getSeconds();
然后计算当前每个针的旋转角度
var secondAngle = seconds;var minuteAngle = minutes * 60 + seconds;var hourAngle = (60/12) * ((hours%12) * 3600 + minuteAngle);
现在的思路就是:每个针会按照自己定的时间转一圈,初始角度也能知道,怎么组成一个显示当前时间的动态钟表呢?
刚开始的想法是让这3层p旋转对应的角度,然后再开始,后来一想不行,因为它还是固定的时间旋转一周,指针指向会有偏差,
现在需要的是页面进来的第一圈旋转固定角度,其余的按照原来固定的时间旋转一周就行了,
css3里面有一个animation-delay属性,它表示的意思是动画延迟,负数就表示提前开始(比如-5s就表示动画从第5s的时间开始),
刚好可以用到,让这几个指针提前开始对应的角度.
js代码如下
hourHand.style.cssText = "animation-delay: -"+ hourAngle +"s";minuteHand.style.cssText = "animation-delay: -"+ minuteAngle +"s";secondHand.style.cssText = "animation-delay: -"+ secondAngle +"s";
最后自己再加了个动态时间在钟表的上面展示
下面是整理后的完整代码,复制粘贴即可使用
CSS
body,html{ margin:0;}.location{ position: relative; width:600px; height:600px; left: calc(50% - 300px);}.dial{ width:600px; height:600px; margin:0 auto; position: absolute; border-radius: 50%; overflow: hidden; background-color: rgba(153,50,204,0.2); background-image: url(img/表盘.jpg); background-size: 100% 100%;}.bigdiv{ width:600px; height:600px; margin:0 auto; position: absolute; border-radius: 50%; overflow: hidden;}.bigdiv>div{ position: absolute; left:298px; border-radius: 100px;}.bigdiv1{ animation: moves 60s steps(60) infinite;}.bigdiv1 .secondHand{ width:4px; height:250px; background-color: red; top:50px; left:298px;}.bigdiv2{ animation: moves 3600s steps(3600) infinite;}.bigdiv2 .minuteHand{ width:6px; height:180px; background-color: green; top:120px; left:297px;}.bigdiv3{ animation: moves 216000s steps(216000) infinite;}.bigdiv3 .hourHand{ width:8px; height:160px; background-color: orange; top:140px; left:296px; border-radius: 100px;}.bigdiv .center{ top:290px; left:290px; width:20px; height:20px; background-color: black; z-index: 2;}@keyframes moves{ from{ transform: rotateZ(0deg); } to{ transform: rotateZ(360deg); }}#dateshow{ text-align: center;}html代码
<h1 id="dateshow"></h1><div class="location"><div class="dial"></div><div class="bigdiv bigdiv1" id="secondHand"> <div class="secondHand"></div></div><div class="bigdiv bigdiv2" id="minuteHand"> <div class="minuteHand"></div></div><div class="bigdiv bigdiv3" id="hourHand"> <div class="center"></div> <div class="hourHand"></div></div></div>
js代码
var dateshow = document.getElementById("dateshow");var clock = { weeks : ["一","二","三","四","五","六","日"], getDate:function(){ date = new Date(); year = date.getFullYear(); month = date.getMonth()+1; day = date.getDate(); hours = date.getHours(); minutes = date.getMinutes(); seconds = date.getSeconds(); week = date.getDay(); // 星期 dateText = year+"年"+month+"月"+clock.format(day)+"日 星期"+clock.formatnum(week)+" "+ clock.format(hours)+":"+clock.format(minutes)+":"+clock.format(seconds); return dateText; }, format:function (data){ if(data.toString().length == 1){ data = "0" + data; }; return data; }, formatnum:function (num){ return clock.weeks[num-1]; }, showdate:function (){ dateshow.innerText = clock.getDate(); }, go:function (){ var secondHand = document.getElementById("secondHand"); var minuteHand = document.getElementById("minuteHand"); var hourHand = document.getElementById("hourHand"); date = new Date(); hours = date.getHours(); minutes = date.getMinutes(); seconds = date.getSeconds(); var secondAngle = seconds; var minuteAngle = minutes * 60 + seconds; var hourAngle = (60/12) * ((hours%12) * 3600 + minuteAngle); hourHand.style.cssText = "animation-delay: -"+ hourAngle +"s"; minuteHand.style.cssText = "animation-delay: -"+ minuteAngle +"s"; secondHand.style.cssText = "animation-delay: -"+ secondAngle +"s"; } }clock.go();clock.showdate();setInterval("clock.showdate()",1000);
