Get ISO date string based on month name

Question

I have to create two ISO date strings in an Array based on the long month name.

Input: 'August'
Output: ['2020-08-01T00:00:00', '2020-08-31T00:00:00']

I am thinking about a switch case to check for each month but I am not sure how to create the ISO string with this information. I could match August with 08 and replace a pre-defined ISO string and replace it based on the input but this doesn't sound very clever.

Answer 1

You can get the month names from toLocaleString for the locale you are in or hardcode an array.

Then calculate the first of this month and the 0th of NEXT month

I had to normalise the time to 15:00 to handle timezones.

const yyyy = new Date().getFullYear();
const months = Array.from(Array(12).keys())
   .map(month => new Date(yyyy, month, 5, 15, 0, 0, 0) 
     .toLocaleString('default', { month: 'long'}) );
const zeroTime = str => `${str.split("T")[0]}T00:00:00`;     
const getDates = month => {
  const monthNum = months.indexOf(month);
  const start = new Date(yyyy, monthNum, 1, 15, 0, 0, 0),
          end = new Date(yyyy, monthNum+1, 0, 15, 0, 0, 0)
  return [zeroTime(start.toISOString()), zeroTime(end.toISOString())];
};
console.log(getDates("August"))