js实现动态时钟
发现一个超级好用的gif图工具"抠抠视频秀"，很好用也不占内存，长这样
- 效果图
- 设计思路
1.调整各个指针的位置关系（
transform-origin:）
2. 计算好各个针之间的度数关系 （分针和时针的度数都不仅仅由自身时间决定）
3. 由于指针初始摆放位置为三点钟方向，所以相对于摆放位置，要正常显示时间需要在计算好的角度基础上-90
关于转动角度的关系具体如下：1 hour=60min =3600s
先分别转动对应针的角度，此时应考虑联动。秒针每秒走6度；
分针每分钟走6度（在考虑秒针对 分针的影响，将秒数换算成分钟）
时针每小时走30度，考虑分针和秒针的影响
- 代码如下
样式
html
<script>
setInterval(function () {
var hours = document.getElementsByClassName("hours")[0];
var minute = document.getElementsByClassName("minute")[0];
var second = document.getElementsByClassName("second")[0];
var date = new Date();
var hour = date.getHours(); //调取当前时间的小时
// console.log(hour);
var min = date.getMinutes(); //调取当前时间的分钟
var sec = date.getSeconds(); //调取当前时间的秒
second.style.transform = "rotate(" + ((sec * 6) - 90) + "deg)";
minute.style.transform = "rotate(" + (((min + (sec / 60)) * 6) - 90) + "deg)";
/* */
hours.style.transform = "rotate(" + (((hour + (sec / 3600) + (min / 60)) * 30) - 90) + "deg)";
/**/
}, 1000)
</script>
最后分享一个见到的实现很棒的动态时钟，但是没有使用图片，而是代码绘制！效果如下
代码如下
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
<style>
/* 全局 */
*{
margin:0;
padding:0;
}
.clock{
width:400px;
height:400px;
border:10px solid #333;
box-shadow: 0 0 20px 3px #444 inset;
border-radius:210px;
position:relative;
margin:5px auto;
z-index:10;
background-color:#f6f6f6;
}
/* 时钟数字 */
.clock-num{
width:40px;
height:40px;
font-size:22px;
text-align:center;
line-height:40px;
position:absolute;
z-index:8;
color:#555;
font-family:fantasy, 'Trebuchet MS';
}
.em_num{
font-size:28px;
}
/* 指针 */
.clock-line{
position:absolute;
z-index:20;
}
.hour-line{width:100px;
height:4px;
top:198px;
left:200px;
background-color:#000;
border-radius:2px;
transform-origin:0 50%;
box-shadow:1px -3px 8px 3px #aaa;
}
.minute-line{
width:130px;
height:2px;
top:199px;
left:190px;
background-color:#000;
transform-origin:7.692% 50%;
box-shadow:1px -3px 8px 1px #aaa;
}
.second-line{
width:170px;
height:1px;
top:199px;
left:180px;
background-color:#f60;
transform-origin:11.765% 50%;
box-shadow:1px -3px 7px 1px #bbb;
}
/* 原点 */
.origin{
width:20px;
height:20px;
border-radius:10px;
background-color:#000;
position:absolute;
top:190px;
left:190px;
z-index:14;
}
/* 日期 时间 */
.date-info{
width:160px;
height:28px;
line-height:28px;
text-align:center;
position:absolute;
top:217px;
left:120px;
z-index:11;
color:#555;
font-weight:bold;
}
.time-info{
width:92px;
height:30px;
line-height:30px;
text-align:center;
position:absolute;
top:270px;
left:154px;
z-index:11;
background-color:#555;
padding:0;
box-shadow:0 0 9px 2px #222 inset;
}
.time{
width:30px;
height:30px;
text-align:center;
float:left;
color:#fff;
font-weight:bold;
}
#minute-time{
border-left:1px solid #fff;
border-right:1px solid #fff;
}
/* 刻度 */
.clock-scale{
width:195px;
height:2px;
transform-origin:0% 50%;
z-index:7;
position:absolute;
top:199px;
left:200px;
}
.scale-show{
width:12px;
height:2px;
background-color:#555;
float:left;
}
.scale-hidden{
width:183px;
height:2px;
float:left;
}
</style>
</head>
<body>
<div class="clock" id="clock">
<!-- 原点 -->
<div class="origin"></div>
<!-- 时分秒针 -->
<div class="clock-line hour-line" id="hour-line"></div>
<div class="clock-line minute-line" id="minute-line"></div>
<div class="clock-line second-line" id="second-line"></div>
<!-- 日期 -->
<div class="date-info" id="date-info"></div>
<!-- 时间 -->
<div class="time-info" >
<div class="time" id="hour-time"></div>
<div class="time" id="minute-time"></div>
<div class="time" id="second-time"></div>
</div>
</div>
<script>
(function(){
window.onload=initNumXY(200, 160, 40,40);
var hour_line = document.getElementById("hour-line");
var minute_line = document.getElementById("minute-line");
var second_line = document.getElementById("second-line");
var date_info = document.getElementById("date-info");
var week_day = [
'星期日', '星期一', '星期二', '星期三', '星期四', '星期五', '星期六'
];
var hour_time = document.getElementById("hour-time");
var minute_time = document.getElementById("minute-time");
var second_time = document.getElementById("second-time");
function setTime(){
var this_day = new Date();
var hour = (this_day.getHours() >= 12) ?
(this_day.getHours() - 12) : this_day.getHours();
var minute = this_day.getMinutes();
var second = this_day.getSeconds();
var hour_rotate = (hour*30-90) + (Math.floor(minute / 12) * 6);
var year = this_day.getFullYear();
var month = ((this_day.getMonth() + 1) < 10 ) ?
"0"+(this_day.getMonth() + 1) : (this_day.getMonth() + 1);
var date = (this_day.getDate() < 10 ) ?
"0"+this_day.getDate() : this_day.getDate();
var day = this_day.getDay();
hour_line.style.transform = 'rotate(' + hour_rotate + 'deg)';
minute_line.style.transform = 'rotate(' + (minute*6 - 90) + 'deg)';
second_line.style.transform = 'rotate(' + (second*6 - 90)+'deg)';
date_info.innerHTML =
year + "-" + month + "-" + date + " " + week_day[day];
hour_time.innerHTML = (this_day.getHours() < 10) ?
"0" + this_day.getHours() : this_day.getHours();
minute_time.innerHTML = (this_day.getMinutes() < 10) ?
"0" + this_day.getMinutes() : this_day.getMinutes();
second_time.innerHTML = (this_day.getSeconds() < 10) ?
"0" + this_day.getSeconds():this_day.getSeconds();
}
setInterval(setTime, 1000);
function initNumXY(R, r, w, h){
var numXY = [
{
"left" : R + 0.5 * r - 0.5 * w,
"top" : R - 0.5 * r * 1.73205 - 0.5 * h
},
{
"left" : R + 0.5 * r * 1.73205 - 0.5 * w,
"top" : R - 0.5 * r - 0.5 * h
},
{
"left" : R + r - 0.5 * w,
"top" : R - 0.5 * h
},
{
"left" : R + 0.5 * r * 1.73205 - 0.5 * w,
"top" : R + 0.5 * r - 0.5 * h
},
{
"left" : R + 0.5 * r - 0.5 * w,
"top" : R + 0.5 * r * 1.732 - 0.5 * h
},
{
"left" : R - 0.5 * w,
"top" : R + r - 0.5 * h
},
{
"left" : R - 0.5 * r - 0.5 * w,
"top" : R + 0.5 * r * 1.732 - 0.5 * h
},
{
"left" : R - 0.5 * r * 1.73205 - 0.5 * w,
"top" : R + 0.5 * r - 0.5 * h
},
{
"left" : R - r - 0.5 * w,
"top" : R - 0.5 * h
},
{
"left" : R - 0.5 * r * 1.73205 - 0.5 * w,
"top" : R - 0.5 * r - 0.5 * h
},
{
"left" : R - 0.5 * r - 0.5 * w,
"top": R - 0.5 * r * 1.73205 - 0.5 * h
},
{
"left" : R - 0.5 * w,
"top" : R - r - 0.5 * h
}
];
var clock = document.getElementById("clock");
for(var i = 1; i <= 12; i++){
if(i%3 == 0) {
clock.innerHTML += ""+i+"";
} else {
clock.innerHTML += "" + i + "";
}
}
var clock_num = document.getElementsByClassName("clock-num");
for(var i = 0; i < clock_num.length; i++) {
clock_num[i].style.left = numXY[i].left + 'px';
clock_num[i].style.top = numXY[i].top + 'px';
}
for(var i = 0; i < 60; i++) {
clock.innerHTML += " " +
"" +
"" +
"";
}
var scale = document.getElementsByClassName("clock-scale");
for(var i = 0; i < scale.length; i++) {
scale[i].style.transform="rotate(" + (i * 6 - 90) + "deg)";
}
}
})();
</script>
</body>
</html>