JS. Advanced JavaScript Questions Breakdown to Crack Any Interview:

 Level            Type

Advanced                             Promises, async/await, event loop, hoisting, this, prototypes, OOP


1. What is a Promise in JavaScript?
➤A Promise represents the eventual result of an asynchronous operation.

2. What is async/await?
➤ A way to write async code that looks synchronous:

async function fetchData() {
    const res=await fetch(url);
}

3. What is hoisting?
➤ JavaScript moves variable and function declarations to the top of their scope before execution.

4. What are the differences between call(), apply(), and bind()?
➤ All are used to set this manually.
  • call() passes args separately
  • apply() passes args as array
  • bind() returns a new function
5. What is the event loop in JavaScript?
➤ It manages execution of code, collecting events, and executing queued sub-tasks (callbacks).


















































Comments

Post a Comment

Popular posts from this blog

PHP INTERVIEW QUESTIONS

      PHP INTERVIEW QUESTIONS 1. WHAT IS PHP? PHP (Hypertext Preprocessor) is a server site scripting language designed for web development. It is widely used foe creating dynamic and interactive website.  2 . Difference between echo and print? echo is faster then print, can print multiple values,  No return value. print slower, return 1 (true) prints on;y one value echo "Hello", " World!";  // ✅ Works print "Hello", " World!"; // ❌ Error 3. Difference between variable and constants?  Both variables and constants store data, but they behave differently.  variable can changeable constants cannot be modify after declaration  variable have local and global scope, while constants are always global  4. what are the different data type in PHP? PHP has 8 primary data types       Data Type Example Description String "Hello"    Sequence of characters Integer 10    Whole number Float 10.5   ...
Read more

PHP Intermediate Questions Interview Preparation

Level          Type Level                                    Arrays, forms, sessions, cookies, file handling, string/date functions 1. What is a PHP session? ➤ Used to store user data across multiple pages. 2. How do you start a session? ➤ Use session_start(); 3.What is a cookie? ➤ Stores small data on the client-side; use setcookie() . 4. How to send a form using PHP? ➤ Use method="post" or method="get" and handle with $_POST or $_GET . 5. How to upload a file in PHP? ➤ Use enctype="multipart/form-data" and handle with $_FILES . 6. How to handle a checkbox or radio in PHP? ➤ Use isset($_POST['checkbox_name']) to check selection. 7. What is the use of explode() function? ➤ Splits a string into an array using a delimiter. 8. What is implode() ? ➤ Joins array elements into a string. 9. How to redirect a page in PHP? ➤ Using h...
Read more

PHP Interview Questions (Beginner Level) – Short Answers

  🔹 PHP Interview Questions (Beginner Level) – Short Answers What is PHP? → PHP is a server-side scripting language used to create dynamic websites. When and why is it used? → Used for web development to handle forms, sessions, databases, and more. What are the main features of PHP? → Open-source, server-side, platform-independent, supports databases. Difference between echo and print ? → echo is faster and can print multiple values; print returns 1 (used in expressions). How do you declare variables in PHP? → With $ symbol. Example: $name = "John"; What are data types in PHP? → String, Integer, Float, Boolean, Array, Object, NULL. Difference between == and === ? → == compares values, === compares value + data type. What are superglobals? → Built-in global variables like $_GET , $_POST , $_SESSION , etc. How does PHP handle forms (GET vs POST)? → $_GET shows data in URL; $_POST hides data. POST is safer for sensitive data. Diff...
Read more