Why is it returning undefined for the month. JS date

Solution 1:

The getMonth() method returns the month in the specified date according to local time, as a zero-based value (where zero indicates the first month of the year). So now in January it return 0. And arr[month-1] would be arr[-1] which is undefined.

Solution 2:

Month is 0-index, so remove the -1 in month-1 will work (if you move January to the beginning of the array).

Since now in January, it will use -1 which is incorrect.

The getMonth() method returns the month in the specified date according to local time, as a zero-based value (where zero indicates the first month of the year).

Correct way to do that:

var date = new Date();
var month = date.getMonth();
var arr = [
   'січня',
   'лютого',
   'березня',
   'квітня',
   'травня',
   'червня',
   'липня',
   'серпня',
   'вересня',
   'жовтня',
   'листопада',
   'грудня',
];
console.log(arr[month])
$('.rf_title').text('Данi оновлено ' + date.getDate() + ' ' + arr[month] + ' ' + date.getFullYear() +' о ' + (date.getHours() < 10 ? '0' + date.getHours() : date.getHours()) + ':' + '' + (date.getMinutes() < 10 ? '0' + date.getMinutes() : date.getMinutes())); 

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