Dart| Flutter: Convert List of Strings into List<int> examples

This tutorial shows multiple ways to Convert List<String> into List<int> in Dart and flutter.

String and int types are different primitive and store different values, So automatic conversion are not possible. You can check on How to convert String to int or vice versa in Dart and flutter.

How to Convert List of String into List of Int type in Dart

This example converts a list of string into a list of int in dart and flutter.

• List has a string of numbers.
• Iterate each element list using the map function.
• map function has a function that applies to each element
• Each element in a string is converted into an int using int.parse
• Finally, returns the elements into a list using toList()

void main() {
  List<String> strs = <String>["11", "12", "5"];
  print(strs.runtimeType);
  List<int> numbers = strs.map(int.parse).toList();
  print(numbers.runtimeType);
  print(numbers);
}

Output:

JSArray<String>
JSArray<int>
[11, 12, 5]

How to parse List of Int into List of String type in Dart

This example converts a list of int into a list of String in dart and flutter.

List of numbers are iterated using map() Each element in the map is applied with toString() to convert to String. Finally, Return list using toList() method

void main() {
  List<int> numbers = <int>[11, 12, 5];
  print(numbers.runtimeType);
  final List<String> strs = numbers.map((e) => e.toString()).toList();

  print(strs.runtimeType);
  print(strs);
}

Output:

JSArray<int>
JSArray<String>
[11, 12, 5]

Conclusion

Learned how to parse and convert a list of strings into a list of numbers and vice versa.