一：转换时间案例
1 需求：
用户输入秒数，系统会自动将秒数转变为小时、分钟、秒，并且不满10的要在前面补零
2 算法：
小时:hour = parseInt(总秒数/60/60%24)
分钟:minute = parseInt(总秒数/60%60)
秒数:second = parseInt(总秒数%60)
3 JS代码实现：
let totalSecond = +prompt('请输入总秒数')function getTime(total = 0) {//函数内没有声明直接使用的变量会变成全局变量let h = parseInt(total / 60 / 60 % 24)let m = parseInt(total / 60 % 60)let s = parseInt(total % 60)h = h < 10 ? '0' + h : hm = m < 10 ? '0' + m : ms = s < 10 ? '0' + s : sreturn (`当前还剩时间${h}小时${m}分${s}秒`)}let surplus = getTime(totalSecond)// document.write(surplus)
console.log(surplus);二：定时轮播图
1 需求：每隔1秒钟切换一张图片
2 最终实现样式：
3 代码：
<!DOCTYPE html>
<html lang="en"><head><meta charset="UTF-8" /><meta http-equiv="X-UA-Compatible" content="IE=edge" /><meta name="viewport" content="width=device-width, initial-scale=1.0" /><title>轮播图点击切换</title><style>* {box-sizing: border-box;}.slider {width: 560px;height: 400px;overflow: hidden;}.slider-wrapper {width: 100%;height: 320px;}.slider-wrapper img {width: 100%;height: 100%;display: block;}.slider-footer {height: 80px;background-color: rgb(100, 67, 68);padding: 12px 12px 0 12px;position: relative;}.slider-footer .toggle {position: absolute;right: 0;top: 12px;display: flex;}.slider-footer .toggle button {margin-right: 12px;width: 28px;height: 28px;appearance: none;border: none;background: rgba(255, 255, 255, 0.1);color: #fff;border-radius: 4px;cursor: pointer;}.slider-footer .toggle button:hover {background: rgba(255, 255, 255, 0.2);}.slider-footer p {margin: 0;color: #fff;font-size: 18px;margin-bottom: 10px;}.slider-indicator {margin: 0;padding: 0;list-style: none;display: flex;align-items: center;}.slider-indicator li {width: 8px;height: 8px;margin: 4px;border-radius: 50%;background: #fff;opacity: 0.4;cursor: pointer;}.slider-indicator li.active {width: 12px;height: 12px;opacity: 1;}</style>
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