MEAN Stack Development MCQ 4

Question 1

Which Angular RxJS operator should you use to cancel a previous HTTP request when a new search term is typed quickly?

Accepted Answer

switchMap

Answer

switchMap cancels the previous inner observable and switches to a new one, making it ideal for typeahead searches to avoid stale responses.

Question 2

What does the `--save-dev` flag do when used with `npm install`?

Accepted Answer

Saves the package as a development-only dependency in devDependencies

Answer

The --save-dev flag adds the package to devDependencies in package.json, indicating it's only needed during development and testing, not in production.

Question 3

In MongoDB, what is the difference between `findOne()` and `find().limit(1)`?

Accepted Answer

findOne() returns a document object while find().limit(1) returns a cursor

Answer

findOne() directly returns a single document (or null), while find().limit(1) returns a cursor that must be iterated to access the document.

Question 4

What is Angular's `HttpInterceptor` primarily used for?

Accepted Answer

To intercept and transform HTTP requests and responses globally

Answer

HttpInterceptor allows you to intercept outgoing requests and incoming responses globally, commonly used for adding auth tokens, logging, or error handling.

Question 5

Which Node.js built-in module provides an interface for working with the operating system?

Accepted Answer

os

Answer

The os module provides operating system-related utility methods and properties like platform, CPU info, free memory, and home directory.

MEAN - Stack Development Practice Test

MEAN - Stack Development Practice Test

MEAN Stack Development MCQ 4