Dart integer Data Type by Examples

In this tutorial, we learn how to use int data type in a Dart program.

How to define int variable and basic operator in Dart

void main() {
  int number1 = 10;
  int number2 = 20;

  int addResult = number1 + number2;
  int subtractResult = number2 - number1;
  int multiplyResult = number1 * number2;
  double divisionResult = number2 / number1;

  int moduloResult = number2 % number1;
  
  print("10 * 20 = " + addResult.toString());
  print("20 -10 = " + subtractResult.toString());
  print("10 * 20 = " + multiplyResult.toString());
  print("20 / 10 = " + divisionResult.toString());
  print("20 % 10 = " + moduloResult.toString());
}

The output is:

10 * 20 = 30
20 -10 = 10
10 * 20 = 200
20 / 10 = 2.0
20 % 10 = 0

Get number of bits using bitLength property

The int class provides bitLength property to return the minimum number of bits needed to store the value in memory.

void main() {
  int number1 = 100;
  print(number1.bitLength);

  int number2 = 1234567890;
  print(number2.bitLength);

  int number3 = 0;
  print(number3.bitLength);

  int number4 = -1;
  print(number4.bitLength);

  int number5 = -1000;
  print(number5.bitLength);
}

The output is:

Check an integer number is even or not using isEven property

void main() {
  int number1 = 0;
  print(number1.isEven);

  int number2 = 1;
  print(number2.isEven);

  int number3 = 2;
  print(number3.isEven);
}

The output is:

true
false
true

Check an integer number is odd or not using isOdd property

void main() {
  int number1 = 0;
  print(number1.isOdd);

  int number2 = 1;
  print(number2.isOdd);

  int number3 = 2;
  print(number3.isOdd);
}

The output is:

false
true
false

Get sign of integer value

void main() {
  int number1 = -100;
  print(number1.sign);

  int number2 = 0;
  print(number2.sign);

  int number3 = 100;
  print(number3.sign);
}

The output is:

-1
0
1

Get absolute value of integer value

void main() {
  int number1 = -100;
  print(number1.abs());

  int number2 = 0;
  print(number2.abs());

  int number3 = 100;
  print(number3.abs());
}

The output is:

100
0
100

Compare two integer values

Dart provides the int.compareTo() method which returns negative if the integer value less than value compared to, zero if it equals and positive value if it greater than value compared to.

void main() {
  int number1 = 10;
  int number2 = 20;
  int number3 = 5;

  print(number1.compareTo(number2));
  print(number1.compareTo(number3));
  print(number1.compareTo(10));
}

The output is:

-1
1
0

Get greatest common divisor value of two integer values

void main() {
  int number1 = 2;
  int number2 = 4;

  print(number1.gcd(number2));
  
  print(1.gcd(5));
}

The output is:

2
1

Convert integer to double value using toDouble method

void main() {
  int number1 = -2;
  int number2 = 0;
  int number3 = 2;

  print(number1.toDouble());
  print(number2.toDouble());
  print(number3.toDouble());
}

The output is:

-2.0
0.0
2.0

Convert integer to String value using toString method

void main() {
  int number1 = -2;
  int number2 = 0;
  int number3 = 2;

  print(number1.toString());
  print(number2.toString());
  print(number3.toString());
}

The output is: