获取两个 Date 对象之间的持续时间(以小时和分钟为单位) - JavaScript

Question

虽然，我在SO上看到了多个类似的问题，但没有一个可以帮助我弄清楚我的计算出了什么问题。我知道我可以使用像Moment这样的库.JS来简化我的解决方案，但我想要原生JavaScript解决方案。

我正在尝试计算两个 Date 对象之间的持续时间(以小时和分钟为单位(，但我得到负(不正确(持续时间。

function padNumber(number, width = 2, padWith = '0') {
const strNum = number.toString();
return strNum.length >= width ? strNum : new Array(width - strNum.length + 1).join(padWith) + strNum;
}
// Get UTC date time from PHP date (Y-m-d) and time (H:i:s) strings
function getUTCDateTime(date, time, timezoneOffset = -480) {
const dateParts = date.split('-').map((el) => Number(el)); // Y-m-d
const timeParts = time.split(':').map((el) => Number(el)); // H:i:s
const dateTimeUTC = new Date(Date.UTC(dateParts[0], dateParts[1], dateParts[2], timeParts[0], timeParts[1], timeParts[2]));
// Set back Singapore specific time (GMT+8:00)
dateTimeUTC.setUTCHours(dateTimeUTC.getUTCHours() + timezoneOffset / 60);
return dateTimeUTC;
}
function getDuration(timeStart, timeEnd = new Date()) {
const msDiff = timeEnd.getTime() - timeStart.getTime();
const minDiff = msDiff / 60000;
const hourDiff = Math.floor(msDiff / 3600000);
return {
hours: this.padNumber(hourDiff, 2),
minutes: this.padNumber(Math.floor(minDiff - 60 * hourDiff), 2)
};
}
// Got from server (in Singapore timezone)
const serverDate = '2018-10-18';
const serverTime = '00:22:51';
// Convert server date and time (timezone specific) strings to Date object
const serverUTC = getUTCDateTime(serverDate, serverTime);
// Get duration between server time and now
const duration = getDuration(serverUTC);
// Expected positive value but getting negative as server time is in past
console.log(duration);

我期望控制台日志中的正值，但我得到负值。我错过了什么吗？

Answer 1

这个问题源于 JavaScript 中月份是从零开始的(即 1 月是0，二月是1，依此类推(。您在getUTCDateTime()中的日期构造不会考虑这一点。

这一行：

const dateTimeUTC = new Date(Date.UTC(dateParts[0], dateParts[1], dateParts[2], timeParts[0], timeParts[1], timeParts[2]));

应该是：

const dateTimeUTC = new Date(Date.UTC(dateParts[0], dateParts[1] - 1, dateParts[2], timeParts[0], timeParts[1], timeParts[2]));

---

完整片段：

function padNumber(number, width = 2, padWith = '0') {
const strNum = number.toString();
return strNum.length >= width ? strNum : new Array(width - strNum.length + 1).join(padWith) + strNum;
}
// Get UTC date time from PHP date (Y-m-d) and time (H:i:s) strings
function getUTCDateTime(date, time, timezoneOffset = -480) {
const dateParts = date.split('-').map((el) => Number(el)); // Y-m-d
const timeParts = time.split(':').map((el) => Number(el)); // H:i:s
const dateTimeUTC = new Date(Date.UTC(dateParts[0], dateParts[1] - 1, dateParts[2], timeParts[0], timeParts[1], timeParts[2]));
// Set back Singapore specific time (GMT+8:00)
dateTimeUTC.setUTCHours(dateTimeUTC.getUTCHours() + timezoneOffset / 60);
return dateTimeUTC;
}
function getDuration(timeStart, timeEnd = new Date()) {
const msDiff = timeEnd.getTime() - timeStart.getTime();
const minDiff = msDiff / 60000;
const hourDiff = Math.floor(msDiff / 3600000);
return {
hours: this.padNumber(hourDiff, 2),
minutes: this.padNumber(Math.floor(minDiff - 60 * hourDiff), 2)
};
}
// Got from server (in Singapore timezone)
const serverDate = '2018-10-18';
const serverTime = '00:22:51';
// Convert server date and time (timezone specific) strings to Date object
const serverUTC = getUTCDateTime(serverDate, serverTime);
// Get duration between server time and now
const duration = getDuration(serverUTC);
// Expected positive value but getting negative as server time is in past
console.log(duration);