本章跟大家介紹如何使用css3與js實現動態時鐘效果，有一定的參考價值，有需要的朋友可以參考一下，希望對你有幫助。
先看看效果圖：
首先,思考了一下頁面的佈局,大致需要4層div,最底層是一個錶盤的背景圖,然後其餘3層分別是時針,分針,秒針的圖層.
html程式碼如下：
<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>變數名稱是隨便起的,不要介意; class=center的這個div是表中心那個小黑點.
時針是60*60*60s轉一圈, 分針是60*60s轉一圈, 秒針是60s轉一圈, 所以css代碼如下：
.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); }
}這一步做完後效果圖是這個樣子的:
然後用js計算當前時間,
var date = new Date(); var hours = date.getHours(); var minutes = date.getMinutes(); var seconds = date.getSeconds();
然後計算當前每個針的旋轉角度
var secondAngle = seconds; var minuteAngle = minutes * 60 + seconds; var hourAngle = (60/12) * ((hours%12) * 3600 + minuteAngle);
現在的思路就是:每個針會按照自己定的時間轉一圈,初始角度也能知道,怎麼組成一個顯示當前時間的動態鐘錶呢?
剛開始的想法是讓這3層div旋轉對應的角度,然後再開始,後來一想不行,因為它還是固定的時間旋轉一周,指針指向會有偏差,
現在需要的是頁面進來的第一圈旋轉固定角度,其餘的按照原來固定的時間旋轉一周就行了,
css3裡面有一個animation-delay屬性,它表示的意思是動畫延遲,負數就表示提前開始(例如-5s就表示動畫從第5s的時間開始),
剛好可以用到,讓這幾個指標提前開始對應的角度.
js程式碼如下：
hourHand.style.cssText = "animation-delay: -"+ hourAngle +"s"; minuteHand.style.cssText = "animation-delay: -"+ minuteAngle +"s"; secondHand.style.cssText = "animation-delay: -"+ secondAngle +"s";
最後自己再加了個動態時間在鐘錶的上面展示
完整程式碼：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
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;
}
</style>
</head>
<body>
<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>
<script>
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);
</script>
</body>
</html>以上是css3+js繪製動態時脈（附程式碼）的詳細內容。更多資訊請關注PHP中文網其他相關文章！
