If you are developing a real-time application where any blocking of the event loop can lead to critical issues, how might you implement a "for" loop to process an array of data without introducing any blockage?

  • Use for...of loop
  • Use setInterval to break up iterations
  • Use for...in loop
  • Use a synchronous for loop with a delay
In a real-time application, using a for...of loop is the recommended approach because it doesn't block the event loop. It iterates through the array without causing delays. Using setInterval is not suitable for processing an array as it introduces an asynchronous behavior. for...in loop is used for object iteration, and a synchronous for loop with a delay would still block the event loop.

A callback function is passed as an ________ to other functions and is executed after its parent function has completed.

  • argument
  • object
  • attribute
  • expression
A callback function is passed as an "argument" to other functions in JavaScript. It is a function that is executed after its parent function has completed its execution. This allows for asynchronous operations and event handling in JavaScript.

Which method returns a promise that resolves with the result of parsing the body text as JSON?

  • .json() method
  • .text() method
  • .body() method
  • .parseJSON() method
The .json() method of a Response object returned by fetch parses the response body text as JSON and returns a Promise that resolves with the parsed data. This method is commonly used when making API requests to obtain structured data in JSON format. The .text() method returns the response body as plain text, while .body() does not exist, and .parseJSON() is not a standard method in JavaScript.

The createElement method is used to create a new element in the _________.

  • browser
  • JavaScript
  • document
  • DOM
The createElement method in JavaScript is used to create a new HTML element within the Document Object Model (DOM). It allows you to dynamically create HTML elements that can be added to the web page or modified as needed.

How can one emulate the functionality of a switch statement using objects and functions in JavaScript?

  • By creating an object where each property maps to a case label, and the corresponding values are functions to execute.
  • By using a for loop to iterate through cases and execute corresponding functions.
  • By using the "continue" keyword in a loop to simulate case behavior.
  • By creating an array of functions, where each function corresponds to a case label.
To emulate the functionality of a switch statement in JavaScript, you can create an object where each property represents a case label, and the corresponding property values are functions that perform the desired actions. You can then use the input value to access the appropriate function from the object, effectively simulating switch behavior.

How do arrow functions handle arguments in comparison to traditional functions?

  • Arrow functions don't have access to arguments.
  • Arrow functions handle arguments the same way as traditional functions.
  • Arrow functions receive arguments as a separate object.
  • Arrow functions receive arguments as individual parameters.
Arrow functions do not have access to the arguments object like traditional functions do. Instead, they handle arguments the same way as regular functions if you explicitly define parameters. Each parameter corresponds to an argument passed to the function, allowing you to access them directly within the function body. The absence of the arguments object can be a limitation in certain scenarios.

Using the new keyword invokes a _______ that creates a new object.

  • constructor
  • function
  • class
  • prototype
Using the new keyword in JavaScript invokes a constructor function that creates a new object. This object is then initialized with properties and methods defined within the constructor function. The constructor function serves as a blueprint for creating objects.

How can Cross-Origin Resource Sharing (CORS) issues be handled when using AJAX?

  • Disable CORS in the browser
  • Use JSONP for requests
  • Send requests with credentials
  • Use the 'Access-Control-Allow-Origin' header
Cross-Origin Resource Sharing (CORS) issues when using AJAX can be handled by configuring the server to include the 'Access-Control-Allow-Origin' header in its response. This header specifies which origins are allowed to access the server's resources. You can set it to '*' to allow any origin or specify specific origins. Additionally, if you need to include credentials (e.g., cookies) in your requests, you should set the 'withCredentials' property to true in your AJAX request.

You're developing a game and need to create multiple instances of a player object, each with slightly different properties. Which object creation pattern might be most appropriate to use?

  • Prototype Pattern
  • Singleton Pattern
  • Factory Method Pattern
  • Abstract Factory Pattern
In game development, you would often use the Factory Method Pattern. This pattern provides an interface for creating objects but allows subclasses to alter the type of objects that will be created. In the context of a game, you can have a PlayerFactory that creates different types of players with varying properties while maintaining a consistent creation interface.

How does the “for...of” loop differ from the traditional "for" loop?

  • It cannot iterate over arrays.
  • It can only be used for asynchronous operations.
  • It is specifically designed for iterating over arrays and iterable objects.
  • It has better performance when iterating over objects.
The "for...of" loop is used for iterating over arrays and iterable objects, providing a simplified syntax compared to the traditional "for" loop. It's particularly useful when dealing with collections of data, offering cleaner code for iteration. Traditional "for" loops are more versatile but require more verbose code for array iteration.