JAVASCRIPT

check if string is valid date

const isDate = (str) => {
  return (new Date(str) !== "Invalid Date") && !isNaN(new Date(str));
}

console.log(isDate('2020-01-01'))
console.log(isDate('abc'))

check if the Date is valid

const isDateValid = (...val) => !Number.isNaN(new Date(...val).valueOf());

isDateValid('December 17, 1995 03:24:00'); // true
isDateValid('1995-12-17T03:24:00'); // true
isDateValid('1995-12-17 T03:24:00'); // false
isDateValid('Duck'); // false
isDateValid(1995, 11, 17); // true
isDateValid(1995, 11, 17, 'Duck'); // false
isDateValid({}); // false