Dart Quiz - MCQ Questions and Answers

Get ready for our Dart Quiz! This set of 25 multiple-choice questions will test your knowledge of Dart, the programming language developed by Google that’s popular for app development, especially with Flutter. 

Whether you’re a beginner just diving into Dart or you have some experience and want to test your skills, this quiz is a great opportunity to see where you stand and learn something new. Let’s get started and explore your Dart expertise!

1. What is Dart primarily used for?

a) Web development

b) Mobile development using Flutter

c) Game development

d) Desktop applications

2. What is the correct way to declare a variable that should not change after being set in Dart?

a) var

b) const

c) let

d) dynamic

3. What type of language is Dart classified as?

a) Statically typed

b) Dynamically typed

c) Both statically and dynamically typed

d) Scripting

4. Which Dart feature allows for creating UI elements or custom widgets in Flutter?

a) Functions

b) Classes

c) Widgets

d) Elements

5. What does the following Dart code print?

void main() {
    print('Dart is fun'.toUpperCase());
}

a) Dart is fun

b) DART IS FUN

c) dart is fun

d) Error

6. How do you define a list of integers in Dart?

a) List<int> numbers = [1, 2, 3];

b) int[] numbers = [1, 2, 3];

c) var numbers = [1, 2, 3];

d) int numbers = [1, 2, 3];

7. Analyze the behavior of the following Dart code:

void main() {
    final names = ['Alice', 'Bob', 'Charlie'];
    names.add('David');
    print(names);
}

a) [Alice, Bob, Charlie]

b) [Alice, Bob, Charlie, David]

c) Error, cannot add to final list

d) None of the above

8. What is the purpose of the await keyword in Dart?

a) Pause function execution until a future completes

b) Repeats a loop execution

c) Error handling

d) None of the above

9. Which is a valid way to define a function that returns no value in Dart?

a) function main() {}

b) void main() {}

c) main() {}

d) None of the above

10. What will the following Dart code output?

void main() {
    var x = 5;
    var result = x is int;
    print(result);
}

a) true

b) false

c) error

d) none of the above

11. What is Dart's null safety feature designed to prevent?

a) Memory leaks

b) Syntax errors

c) Null dereference errors

d) Compilation errors

12. How do you declare a multi-line string in Dart?

a) Using single quotes (' ')

b) Using double quotes (" ")

c) Using triple quotes (''' ''')

d) Using backticks ( )

13. Consider the following Dart function. What is its return type?

bool isEven(int number) {
    return number % 2 == 0;
}

a) int

b) double

c) bool

d) void

14. What does the ?. operator do in Dart?

a) It is a null-aware operator that allows methods or properties to be accessed on an object only if that object is not null.

b) It ensures that an object is not null before calling any of its methods.

c) It creates a new instance of an object if the existing one is null.

d) It throws an exception if the accessed variable is null.

15. How do you handle exceptions in Dart?

a) Using the error block

b) Using the catch block

c) Using the finally block

d) Using the except block

16. What will the following Dart code print?

void main() {
    int? age;
    print(age ?? 'Unknown');
}

a) 0

b) null

c) 'Unknown'

d) Error

17. In Dart, what does the extends keyword do?

a) It is used to create a new class that inherits properties and methods from another class.

b) It is used to implement an interface.

c) It is used to define a mixin.

d) It is used to declare an abstract class.

18. What is the Dart equivalent of a JavaScript arrow function?

a) Lambda

b) Fat arrow function

c) Single-line function

d) There is no equivalent

19. What feature allows Dart functions to skip specifying the types?

a) Dynamic typing

b) Type inference

c) Optional typing

d) Strong typing

20. What does the following code snippet demonstrate in Dart?

void main() {
    List<String> names = ['Alice', 'Bob', 'Charlie'];
    for (var name in names) {
        print(name);
    }
}

a) List iteration using a for loop

b) Map creation

c) Set enumeration

d) None of the above

21. What Dart construct is used to group functions, variables, and other types together?

a) Package

b) Library

c) Module

d) Script

22. What will the following Dart code print?

void main() {
    var numbers = [1, 2, 3];
    numbers.add(4);
    print(numbers.length);
}

a) 3

b) 4

c) 5

d) Error

23. How is immutability enforced in Dart for a list?

a) Using the immutable keyword

b) Using the final keyword

c) Using the const keyword

d) It cannot be enforced

24. Consider the following Dart function. What is the error in this code?

int addNumbers(int a, int b) {
    return a + b;
    print('Total: ${a + b}');
}

a) Syntax error

b) Logical error, as the print statement will never execute

c) The function should not return a value

d) There is no error

25. What does the expand method do for lists in Dart?

a) Shrinks the list by removing elements

b) Concatenates multiple lists into a single list

c) Transforms each element into a sequence of elements

d) None of the above