第 28 张证书：林继老师：您

。第 28 张证书林继老师您从事乡村教育工作满二十年，为我省乡村教育发展做出积极贡献，特颁此证。证书编号系列号0024761。广东省教育厅 二0二三年八月执教23年3月11天9时 45分3秒             判断是否为闰年的函数        function isLeapYearyear             return year  4  0  year  100 0  year  400  0                 计算两个日期之间时间差，并精确计算月份差的函数        function calculateTimeDifferencestartDate, endDate             const diffInMilliseconds  endDate  startDate             先计算完整的年份差            const years  MathfloordiffInMilliseconds  1000  60  60  24  365             扣除已计算的年份对应的毫秒数，得到剩余毫秒数用于后续计算            let remainingMilliseconds  diffInMilliseconds  1000  60  60  24  365             计算月份差，通过逐月递减剩余毫秒数并统计月份            let months  0            const monthsInYear  31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31            const startYear  startDategetFullYear            for let i  0 i  12 i                 const daysInMonth  i  1  isLeapYearstartYear  years 29  monthsInYeari                const millisecondsInMonth  1000  60  60  24  daysInMonth                if remainingMilliseconds  millisecondsInMonth                     months                    remainingMilliseconds  millisecondsInMonth                 else                     break                                         计算天数差            const days  MathfloorremainingMilliseconds  1000  60  60  24            remainingMilliseconds  1000  60  60  24             计算小时差            const hours  MathfloorremainingMilliseconds  1000  60  60            remainingMilliseconds  1000  60  60             计算分钟差            const minutes  MathfloorremainingMilliseconds  1000  60            remainingMilliseconds  1000  60             计算秒数差            const seconds  MathfloorremainingMilliseconds  1000            return                 years,                months,                days,                hours,                minutes,                seconds                            function updateClockelementId, startDateStr             const startDate  new DatestartDateStr            startDatesetTimestartDategetTime  8  60  60  1000  转换为北京时间            function updateTimeDisplay2                 const endDate  new Date                endDatesetTimeendDategetTime  8  60  60  1000  转换为北京时间                const  years, months, days, hours, minutes, seconds   calculateTimeDifferencestartDate, endDate                documentgetElementByIdelementIdinnerHTML  years年months月days天hours时minutes分seconds秒                         每隔1秒更新一次时间差显示            setIntervalupdateTimeDisplay2, 1000                updateClocktxClock, 20010901T000000