The rule is if value >= 500,000 it will be rounded up to 1,000,000, if the value < 500,000 it will be rounded down to 000,000
Here an example, if I have value like 4,843,820,00 it will be rounded up to 4,844,000,000
If I have value like 1,136,362,500 it will be rounded down to 1,136,000,000
If I have value like 1,500,000 will be rounded up to 2,000,000 & if I have like 1,450,000 it will be rounded down to 1,000,000

Here is what I tried

String kmbGenerator(number) {
    if (number > 999 && number < 99999) {
      int resulta = (number / 1000).round();
      return "$resulta,000";
    } else if (number > 99999 && number < 999999) {
      int resulta = (number / 1000).round();
      return '${resulta.toStringAsFixed(0)},000';
    } else if (number > 999999 && number < 999999999) {
      int resulta = (number / 1000000).round();
      return "$resulta,000,000";
    } else if (number > 999999999) {
      int resulta = (number / 1000000000).round();
      return "$resulta,000,000,000";
    } else {
      return number.toString();
    }
  }

CodePudding user response：

Divide by one million, round, then multiply by one million:

int roundMillions(int value) {
  return (value / 1e6).round() * 1000000;
}

main() {
  void test(int value) {
    print('rounded $value to ${roundMillions(value)}');
  }
  test(4843820000);
  test(1136362500);
  test(1500000);
  test(1450000);
}

Output:

rounded 4843820000 to 4844000000
rounded 1136362500 to 1136000000
rounded 1500000 to 2000000
rounded 1450000 to 1000000

CodePudding user response：

Before you format round it using num.round() for example if you want to round to millions :

double n = 29971800;
double roundTo = 1000000; //million
print((n/roundTo).round()); //prints 30

you can either multiply it by million and format it or just convert to String and add ',000,000'

CodePudding user response：

another way is using ~/ and multiplying to million example (123456789~/1000000) * 1000000

use this function

int roundMillion(int val) => (val~/1000000) * 1000000;