{

How to Check given number is an integer or whole number or decimal number in dart | Flutter By Example


In Dart, We have two numerical types - int, double

int represents whole numbers, that contain no fractional or decimal digits double stores the floating numbers that contain decimal values.

how to check given number is int or double?

There are multiple ways we can check

  • using is Operator

dart is the operator used to check the variable of a given type or not

Syntax:

variable is datatype

Returns true if the variable of a given datatype else returns false. This check is added as an extension to num type.

Here is an example program to check given number is int or double.

void main() {
  num intValue = 12;
  num doubleValue = 11.12;
  print(intValue.isIntValue()); // true
  print(doubleValue.isIntValue()); // false
}

extension WholeNumber on num {
  bool isIntValue() => this is int;
}

  • using Modulus Operator

The modulus operator gives a remainder after two operand divisions.

if the given number is a whole number, Then the value is divided by 1 and gives the remainder as zero if the given number is a double or fractional decimal value, Then the remainder is not zero after division by 1

Here is an example program to check given number contains a fractional decimal or not.

void main() {
  num intValue = 12;
  num doubleValue = 11.12;
  print(intValue.isIntValue()); // true
  print(doubleValue.isIntValue()); // false
}

extension WholeNumber on num {
  bool isIntValue() => (this % 1) == 0;
}


  • use toInt method

The given number is truncated using the toInt method. If the given number is 11.12, toInt returns int number i.e 11. Checks the original value and result, if both are equal, It is an integer number.

Here is an example program

void main() {
  num intValue = 12;
  num doubleValue = 11.12;
  print(intValue.isIntValue()); // true
  print(doubleValue.isIntValue()); // false
}

extension WholeNumber on num {
  bool isIntValue() => this ==this.toInt();
}

Conclusion

There are multiple ways to check given a number is a whole number or fractional decimal number in dart examples below approaches.

  • use toInt method
  • dart is the operator
  • using Modulus Operator
THE BEST NEWSLETTER ANYWHERE
Join 6,000 subscribers and get a daily digest of full stack tutorials delivered to your inbox directly.No spam ever. Unsubscribe any time.

Similar Posts
Subscribe
You'll get a notification every time a post gets published here.





Related posts

Dart| Flutter How to: Find a Given String is numeric or not

How to iterate loop Enum in Dart | Get Enum with index in Flutter By Example

Dart Enum comparison operator| Enum compareByIndex example| Flutter By Example

Dart tutorial examples/ Flutter By Examples

How to add Methods or Values to Enums in Dart | Flutter By Example

How to convert Double to Integer or Integer to double in Dart| Flutter By Example

How to: Enum to String in Dart | Print Enum name as String in Flutter By Example