dateDifference static method

DateDuration dateDifference({
  1. required DateTime fromDate,
  2. required DateTime toDate,
})

dateDifference method

Implementation

static DateDuration dateDifference({
  required DateTime fromDate,
  required DateTime toDate,
}) {
  // Check if toDate to be included in the calculation
  DateTime endDate = toDate;

  int years = endDate.year - fromDate.year;
  int months = 0;
  int days = 0;

  if (fromDate.month > endDate.month) {
    years--;
    months = (DateTime.monthsPerYear + endDate.month - fromDate.month);

    if (fromDate.day > endDate.day) {
      months--;
      days = daysInMonth(fromDate.year + years,
              ((fromDate.month + months - 1) % DateTime.monthsPerYear) + 1) +
          endDate.day -
          fromDate.day;
    } else {
      days = endDate.day - fromDate.day;
    }
  } else if (endDate.month == fromDate.month) {
    if (fromDate.day > endDate.day) {
      years--;
      months = DateTime.monthsPerYear - 1;
      days = daysInMonth(fromDate.year + years,
              ((fromDate.month + months - 1) % DateTime.monthsPerYear) + 1) +
          endDate.day -
          fromDate.day;
    } else {
      days = endDate.day - fromDate.day;
    }
  } else {
    months = (endDate.month - fromDate.month);

    if (fromDate.day > endDate.day) {
      months--;
      days = daysInMonth(fromDate.year + years, (fromDate.month + months)) +
          endDate.day -
          fromDate.day;
    } else {
      days = endDate.day - fromDate.day;
    }
  }

  return DateDuration(days: days, months: months, years: years);
}