- Difference between
nullis an intentional absence of value, while
undefinedis a default value for an undeclared variable. 🚫🔍
- Closures: The Inside Scoop Closures are functions retaining access to outer function variables even after execution. Powerful for encapsulating behavior! 🔐🔒
- Demystifying the
thisrefers to a function’s context. It’s pivotal for accessing object properties and methods. 💼🧩
- Prototypal Inheritance Deep Dive Objects can inherit properties via prototype chains. If it’s not found in the object, the chain search begins. 🧬🔗
- Event Delegation: Efficient Handling Handle events by attaching listeners to a common ancestor, saving resources and adapting to dynamic content. 📡🎯
symbol. Plus, non-primitive:
- Asynchronous Programming Unveiled Asynchronous programming juggles background tasks, allowing non-blocking execution. Crucial for responsive applications. ⏰⚙️
thisThese methods tame the
bindcrafts a new function,
applytrigger functions immediately. 🤝📞
- Error Handling 101:
try...catchHandle runtime errors with grace using
try...catch. Execute code in
tryand manage exceptions in
2. What is the difference between
nullrepresents the intentional absence of any value.
undefinedis the default value of a variable that has been declared but not assigned a value.
- Answer: A closure is a function that retains access to variables from its outer (enclosing) function even after the outer function has finished executing. This allows the inner function to continue referencing those variables.
4. What is the purpose of the
- Answer: The
thiskeyword refers to the context in which a function is executed. It can be affected by how the function is called, and it helps to access properties and methods of an object.
- Answer: Event delegation involves attaching an event listener to a common ancestor of multiple elements, instead of attaching listeners to each individual element. This is useful for improving performance and handling dynamic content.
symbol(ES6). It also has a non-primitive data type:
- Answer: Asynchronous programming allows tasks to run in the background while the main program continues to execute. This is crucial for handling tasks like network requests, timers, and user input without blocking the main thread.
9. What is the purpose of the
- Answer: These methods are used to control the value of the
thiskeyword when calling a function.
bindcreates a new function with a fixed
applyimmediately invoke the function with the provided
thisvalue and arguments.
try...catchstatement for handling runtime errors. Code inside the
tryblock is executed, and if an exception is thrown, it’s caught and processed in the
Remember that interview questions may vary in complexity, and understanding the underlying concepts is key to providing strong answers. These answers provide a general overview; feel free to elaborate further during interviews.