Question 1: What is TypeScript?

Answers

a) A front-end framework

b) A superset of JavaScript

c) A database management system

d) A back-end programming language

Question 2: How do you compile a TypeScript file to JavaScript?

Answers

a) tsc filename.js

b) compile filename.ts

c) tsc filename.ts

d) typescript filename.ts

Question 3: Which of the following is a correct way to define a variable with a specific type in TypeScript?

Answers

a) let age = number;

b) let age: number;

c) let age: Number;

d) let age: int;

Question 4: How do you define an interface in TypeScript?

Answers

a) class InterfaceName {}

b) interface InterfaceName {}

c) struct InterfaceName {}

d) type InterfaceName = {};

Question 5: What is the purpose of the readonly modifier in TypeScript?

Answers

a) To prevent the variable from being assigned a value initially

b) To allow the variable to be modified only within a specific scope

c) To ensure that a property cannot be modified after it is initialized

d) To automatically generate getter and setter methods for the property

Question 6: How do you declare a tuple type in TypeScript?

Answers

a) let myTuple: [number, string];

b) let myTuple: (number, string);

c) let myTuple: {number, string};

d) let myTuple: number[];

Question 7: What is the never type used for in TypeScript?

Answers

a) To represent a variable that can hold any value

b) To indicate a variable that can hold only null or undefined

c) To represent a function that always throws an exception or never returns

d) To specify an optional parameter in a function

Question 8: Which of the following TypeScript features is not available in plain JavaScript?

Answers

a) Arrow functions

b) Generics

c) Promises

d) Template literals

Question 9: What does the unknown type represent in TypeScript?

Answers

a) A type that is equivalent to any and can be assigned to any other type

b) A type that forces you to do a type check before using it

c) A type that represents a function that never returns

d) A type that can only be null or undefined

Question 10: How can you ensure that a variable can only have specific values in TypeScript?

Answers

a) Using an enum

b) Using an interface

c) Using a union type

d) Using a class

Question 11: How do you create a default parameter in a TypeScript function?

Answers

a) function myFunction(param: type = defaultValue) {}

b) function myFunction(param = defaultValue: type) {}

c) function myFunction(param: type) = defaultValue {}

d) function myFunction(param = defaultValue): type {}

Question 12: What is the difference between interface and type in TypeScript?

Answers

a) interface is used to define objects only, while type can define any data structure.

b) type is used for classes, and interface is used for functions.

c) interface can be merged, while type cannot.

d) type supports inheritance, while interface does not.

Question 13: How do you apply decorators in TypeScript?

Answers

a) By using the @ symbol before a class or method

b) By using the # symbol before a class or method

c) By using the & symbol before a class or method

d) By using the * symbol before a class or method

Question 14: What is the correct way to cast a variable from one type to another in TypeScript?

Answers

a) let var2 = <number> var1;

b) let var2: number = var1;

c) let var2 = (number) var1;

d) let var2 = number(var1);

Question 15: Which keyword is used to inherit from a class in TypeScript?

Answers

a) inherits

b) extends

c) implements

d) super

TypeScript Questions

Question 1: What is TypeScript?

Question 2: How do you compile a TypeScript file to JavaScript?

Question 3: Which of the following is a correct way to define a variable with a specific type in TypeScript?

Question 4: How do you define an interface in TypeScript?

Question 5: What is the purpose of the readonly modifier in TypeScript?

Question 6: How do you declare a tuple type in TypeScript?

Question 7: What is the never type used for in TypeScript?

Question 8: Which of the following TypeScript features is not available in plain JavaScript?

Question 9: What does the unknown type represent in TypeScript?

Question 10: How can you ensure that a variable can only have specific values in TypeScript?

Question 11: How do you create a default parameter in a TypeScript function?

Question 12: What is the difference between interface and type in TypeScript?

Question 13: How do you apply decorators in TypeScript?

Question 14: What is the correct way to cast a variable from one type to another in TypeScript?

Question 15: Which keyword is used to inherit from a class in TypeScript?