Lists in Dart

What is a List?

A List is an ordered collection of items. Lists allow duplicate values and maintain insertion order. They are the most commonly used collection type in Dart.

Creating Lists

// Fixed-type list
List<int> numbers = [1, 2, 3, 4, 5];
List<String> names = ['Alice', 'Bob', 'Carol'];

// Type inference
var fruits = ['apple', 'banana', 'cherry'];

// Empty list
List<double> scores = [];

// Fixed-length list (cannot add/remove)
var fixed = List<int>.filled(5, 0); // [0, 0, 0, 0, 0]

// Generated list
var squares = List<int>.generate(5, (i) => (i + 1) * (i + 1));
// [1, 4, 9, 16, 25]

Accessing Elements

var fruits = ['apple', 'banana', 'cherry'];
print(fruits[0]);          // apple (first)
print(fruits.last);        // cherry (last)
print(fruits.length);      // 3
print(fruits.isEmpty);     // false
print(fruits.isNotEmpty);  // true

Common Methods

Example

void main() {
  List<String> tasks = ['Write code', 'Test code', 'Deploy'];

  tasks.add('Monitor');
  tasks.insert(0, 'Plan');
  print(tasks);  // [Plan, Write code, Test code, Deploy, Monitor]

  tasks.remove('Test code');
  print(tasks.length);      // 4

  print(tasks.contains('Deploy'));  // true
  print(tasks.indexOf('Deploy'));   // 2

  var numbers = [3, 1, 4, 1, 5, 9, 2, 6];
  numbers.sort();
  print(numbers);           // [1, 1, 2, 3, 4, 5, 6, 9]
  print(numbers.sublist(2, 5)); // [2, 3, 4]
}

[Plan, Write code, Test code, Deploy, Monitor]
4
true
2
[1, 1, 2, 3, 4, 5, 6, 9]
[2, 3, 4]

🧠 Quiz

Summary

Dart Lists are ordered, indexed, and allow duplicates. Create them with literal syntax [...] or List.generate(). Key methods: add(), remove(), sort(), contains(), sublist(). Access elements by index (zero-based) or with .first/.last.