Dart Control Flow Statements: Complete Guide with Examples and Outputs

Arp Cloud Store Admin June 07, 2026


Dart Control Flow Statements: Complete Guide with Examples and Outputs

Control Flow Statements are one of the most important concepts in Dart programming. They determine how your program makes decisions, repeats tasks, and controls the execution of code. Every Flutter developer should have a strong understanding of these concepts because they are used in almost every application.

What is Control Flow?

Control Flow refers to the order in which the statements of a program are executed. By default, Dart executes code from top to bottom. However, using control flow statements, we can make decisions, execute code repeatedly, or skip certain parts of the program.


 

Dart Control Flow Statements: Complete Guide with Examples and Outputs


1. If Statement

The if statement executes a block of code only when a specified condition is true.

Syntax

if (condition) {
  // code
}

Example

int age = 18;

if (age >= 18) {
  print("Eligible to vote");
}

Output

Eligible to vote

In this example, the condition is true, so the code inside the if block gets executed.

2. If-Else Statement

The if-else statement is used when there are two possible outcomes.

Example

int age = 16;

if (age >= 18) {
  print("Adult");
} else {
  print("Minor");
}

Output

Minor

Since the condition is false, the else block executes.

3. Else-If Ladder

The else-if ladder allows multiple conditions to be checked one after another.

Example

int marks = 85;

if (marks >= 90) {
  print("Grade A");
} else if (marks >= 80) {
  print("Grade B");
} else if (marks >= 70) {
  print("Grade C");
} else {
  print("Fail");
}

Output

Grade B

Dart checks conditions from top to bottom and executes the first matching block.

4. For Loop

A for loop is used when the number of iterations is known in advance.

Example

for (int i = 1; i <= 5; i++) {
  print(i);
}

Output

1
2
3
4
5

The loop starts from 1 and continues until the condition becomes false.

5. While Loop

The while loop executes as long as a condition remains true.

Example

int i = 1;

while (i <= 5) {
  print(i);
  i++;
}

Output

1
2
3
4
5

The condition is checked before each iteration.

6. Do-While Loop

The do-while loop executes at least once, even if the condition is false.

Example

int i = 5;

do {
  print(i);
} while (i < 3);

Output

5

The code executes once before checking the condition.

7. Break Statement

The break statement immediately terminates a loop.

Example

for (int i = 1; i <= 5; i++) {
  if (i == 3) {
    break;
  }

  print(i);
}

Output

1
2

When i becomes 3, the loop stops completely.

8. Continue Statement

The continue statement skips the current iteration and moves to the next one.

Example

for (int i = 1; i <= 5; i++) {

  if (i == 3) {
    continue;
  }

  print(i);
}

Output

1
2
4
5

The value 3 is skipped while the loop continues executing.

9. Switch Case

The switch statement is used when there are multiple fixed choices.

Example

String day = "Monday";

switch (day) {

  case "Monday":
    print("Start of Week");
    break;

  case "Friday":
    print("Weekend Coming");
    break;

  default:
    print("Normal Day");
}

Output

Start of Week

Switch statements improve readability when checking multiple constant values.

10. Ternary Operator ( ? : )

The ternary operator is a shorthand version of if-else.

Example

int age = 20;

String result =
    age >= 18 ? "Adult" : "Minor";

print(result);

Output

Adult

This is useful when assigning values based on a condition.

11. Null Coalescing Operator ( ?? )

The null coalescing operator provides a default value when a variable is null.

Example

String? name;

print(name ?? "Guest");

Output

Guest

This operator is very common in Flutter applications for handling nullable values.

When Should You Use Which Statement?

Statement Purpose
if Single condition check
if-else Two possible outcomes
else-if Multiple conditions
for Known number of iterations
while Unknown iterations
do-while Execute at least once
break Stop loop execution
continue Skip current iteration
switch Multiple fixed choices
?: Short if-else
?? Default value for null

Conclusion

Control Flow Statements are the foundation of Dart programming. They help developers make decisions, repeat tasks, and write efficient code. Whether you are preparing for Flutter interviews or building real-world applications, mastering if-else statements, loops, switch cases, and conditional operators will significantly improve your coding skills.

Practice these concepts regularly and try combining multiple control flow statements to solve real-world programming problems.

Also Read

Tags