Saviynt React Js Frontend Developer Interview Questions, Process, and Tips

Convert a counter code from class component to functional component

• Use useState hook to manage state in functional component

• Remove 'this' keyword and constructor from the code

• Update event handlers to use arrow functions or useCallback hook

Code snippet to post data to a public URL in React

• Use the fetch API to make a POST request to the public URL

• Convert the data to JSON before sending it in the request body

• Handle the response from the server accordingly

Arrow functions are more concise and have lexical scoping, while normal functions have their own 'this' value.

• Arrow functions do not have their own 'this' value, they inherit it from the parent scope.

• Arrow functions are more concise and have implicit return.

• Normal functions are more flexible and can be used as constructors.

• Arrow functions cannot be used as constructors.

• Arrow functions do not have 'arguments' object.

Call stack stores function calls and local variables, while heap stores dynamic memory allocation.

• Call stack is used for function calls and local variables

• Heap is used for dynamic memory allocation

• Call stack is limited in size and has a fixed memory allocation, while heap is larger and can grow dynamically

• Example: Call stack is used to keep track of function calls in a recursive function, while heap is used to allocate

CORS stands for Cross-Origin Resource Sharing and is a security feature implemented by browsers to prevent unauthorized access to resources on a different domain.

• CORS allows servers to specify who can access their resources by adding specific HTTP headers to their responses.

• It is used to protect against cross-site request forgery (CSRF) attacks.

• For example, if a frontend application on domain A tries to make a request ...read more

Map two arrays of objects and display results in lists using React

• Use the map function to iterate over each array of objects

• Render the results in separate lists using JSX

• Example: array1.map(item =>

• {item.name}
)