Add/Subtract months/years to date in dart?

Question

I saw that in dart there is a class Duration but it cant be used add/subtract years or month. How did you managed this issue, I need to subtract 6 months from an date. Is th

Answer 1

You can use subtract and add methods

Subtract

Add

But you have to reassign the result to the variable, which means:

This wouldn't work

 date1.add(Duration(days: 1, hours: 23)));

But this will:

 date1 = date1.add(Duration(days: 1, hours: 23)));

For example:

 void main() {
  var d = DateTime.utc(2020, 05, 27, 0, 0, 0);
  d.add(Duration(days: 1, hours: 23));
  // the prev line has no effect on the value of d
  print(d); // prints: 2020-05-27 00:00:00.000Z

  //But
  d = d.add(Duration(days: 1, hours: 23));
  print(d); // prints: 2020-05-28 23:00:00.000Z
}

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