如何将 ISO 8601 日期+时间字符串从 Firebase 转换为 JavaScript 中的“日期”值？

Question

I have this firebase Timestamp dates:

time1: "2021-02-19T15:23:47.747Z"
time2: "2021-02-19T15:28:04.331Z"

and I need to convert these dates to normal dates. I want to do this in Javascript. How can I do this?

Answer 1

You can get ms timestamp with:

new Date(time1).getTime()

Answer 2

You should use Date.parse() to convert your string to milliseconds. You can then convert that into whatever you need.

 const time1 = convertTimestamp("2021-02-19T15:23:47.747Z"); const time2 = convertTimestamp("2021-02-19T15:28:04.331Z"); function convertTimestamp(dateStr) { const start = Date.parse(dateStr); let now = new Date(0); // The 0 is important now.setUTCMilliseconds(start); const output = now.getUTCFullYear() +"/"+ (now.getUTCMonth()+1) +"/"+ now.getUTCDate() + " " + now.getUTCHours() + ":" + now.getUTCMinutes(); document.body.append(output + ' '); return output; }

Avoid the new Date(dateString) format as it doesn't have consistent behavior over different environments.

Answer 3

You can convert it like that:

new Date('2021-02-19T15:23:47.747Z').toGMTString().split(' ')
// ["Fri,", "19", "Feb", "2021", "15:23:47", "GMT"]

Or

let converted = new Date('2021-02-19T15:23:47.747Z').toGMTString().split(' ');
let date = {
    year: converted[3],
    month: converted[2],
    day: converted[1],
    time: converted[4],
    timezone: converted[5]
}

// day: "19"
// month: "Feb"
// time: "15:23:47"
// timezone: "GMT"
// year: "2021"