如何使用 Moment js 从 ISO 日期获取月份名称

Question

I am trying to extract the month name from ISO dates.

I am trying this:

moment('2020-01-01T00:00:00.000Z', 'YYYY-MM-DDTHH:mm:ss.SSS[Z]').month('MMMM');

I am getting invalid date .

How can I extract the month name and the week number from ISO dates?

Answer 1

As I mentioned in a comment, use .format() instead:

moment('2020-01-01T00:00:00.000Z', 'YYYY-MM-DDTHH:mm:ss.SSS[Z]').format('MMMM');

Answer 2

You should use format() method. https://momentjs.com/docs/#/parsing/

var month = moment('2020-01-01T00:00:00.000Z', 'YYYY-MM-DDTHH:mm:ss.SSS[Z]').format('MMMM');

Answer 3

There is already an answer for doing this with moment.js, so for completeness here's one for using toLocaleString . Note that the input string needs to be compliant with the format specified by ECMA-262 .

One issue to consider is whether you want the UTC month or user's local month. For users with a negative timezone offset, '2020-01-01T00:00:00.000Z' is in December, not January, eg:

 let d = new Date('2020-01-01T00:00:00.000Z'); // Zero offset let utcMonth = d.toLocaleString('en',{month:'long', timeZone:'UTC', timeZoneName: 'long'}); // Negative offset let spMonth = d.toLocaleString('en',{month:'long', timeZone:'America/Sao_Paulo', timeZoneName: 'long'}); console.log('The UTC month is: ' + utcMonth + '\nSao Paulo month is: ' + spMonth);

By specifying the timezone as UTC, it ensures that users with a negative timezone offset get January, not their local month which will be December.