Dart Loops
Dart provides several looping constructs that allow you to iterate over a set of instructions multiple times. Here’s an overview of the common loop types in Dart with examples:
1. while Loop
The while loop executes a block of code as long as the condition is true.
void main() {
int i = 0;
while (i < 5) {
print('Iteration $i');
i++;
}
}
2. do-while Loop
The do-while loop is similar to the while loop, but it guarantees that the loop body will be executed at least once.
void main() {
int i = 0;
do {
print('Iteration $i');
i++;
} while (i < 5);
}
3. for Loop
The for loop is used to execute a block of code a specified number of times.
void main() {
for (int i = 0; i < 5; i++) {
print('Iteration $i');
}
}
4. for-in Loop
The for-in loop is used to iterate over the elements of a collection (like a list or a set).
void main() {
List fruits = ['Apple', 'Banana', 'Cherry'];
for (var fruit in fruits) {
print(fruit);
}
}
5. forEach Loop
The forEach method is used to execute a function for each element in a collection.
void main() {
List numbers = [1, 2, 3, 4, 5];
numbers.forEach((number) {
print('Number: $number');
});
}
6. Nested Loops
You can nest loops within each other to perform more complex iterations.
void main() {
for (int i = 1; i <= 3; i++) {
for (int j = 1; j <= 2; j++) {
print('i: $i, j: $j');
}
}
}
7. break and continue Statements
The break statement exits the loop immediately, and the continue statement skips to the next iteration of the loop.
Using break:
void main() {
for (int i = 0; i < 5; i++) {
if (i == 3) {
break;
}
print('Iteration $i');
}
}
Using continue:
void main() {
for (int i = 0; i < 5; i++) {
if (i == 3) {
continue;
}
print('Iteration $i');
}
}
Dart Loop Exercises
Try solving the following exercises using Dart loops:
