For Loop in Dart

Syntax

The for loop repeats a block of code a specific number of times. It has three parts: initializer, condition, and increment.

for (initializer; condition; increment) {
  // code to repeat
}

Example

void main() {
  // Count 1 to 5
  for (int i = 1; i <= 5; i++) {
    print('Count: $i');
  }

  // Sum of 1 to 100
  int sum = 0;
  for (int i = 1; i <= 100; i++) {
    sum += i;
  }
  print('Sum 1–100: $sum');  // 5050

  // Loop backwards
  for (int i = 5; i >= 1; i--) {
    print('Countdown: $i');
  }
}

Count: 1
Count: 2
Count: 3
Count: 4
Count: 5
Sum 1–100: 5050
Countdown: 5 ... 1

For-In Loop

Iterate over every element in a collection without a counter:

List<String> fruits = ['apple', 'banana', 'cherry'];
for (String fruit in fruits) {
  print(fruit);
}
// apple  banana  cherry

forEach()

Collections also have a forEach() method that accepts a function:

fruits.forEach((fruit) => print(fruit.toUpperCase()));
// APPLE  BANANA  CHERRY

🧠 Quiz

Summary

The for loop repeats a block a set number of times with an initializer, condition, and increment. Use for-in to iterate over collections. Use forEach() for functional-style iteration with a callback.