Which of the following correctly defines a JavaScript function?
A). A. function addNumbers(num1, num2) { return num1 + num2; }
B). B. function = addNumbers(num1, num2) { return num1 + num2; }
C). C. function addNumbers(num1 + num2) { return num1 + num2; }
D). D. function addNumbers(num1, num2) => { return num1 + num2; }
How can you prevent the default behavior of an event in JavaScript?
A). A. By using the event.preventDefault() method inside the event handler function
B). B. By using the event.stopPropogation() method inside the event handler function
C). C. By using the event.stopPropagation() method inside the event handler function
D). D. By using the event.defaultPrevented property inside the event handler function
Consider the following JavaScript code: let greet = function(name) { return 'Hello, ' + name + '!'; }; What type of function is greet in this code?
A). A. Named function
B). B. Anonymous function
C). C. Arrow function
D). D. Generator function
What does the preventDefault() method do in JavaScript event handling?
A). A. Stops event propagation to parent elements
B). B. Prevents the default behavior associated with an event
C). C. Detaches event listeners from elements
D). D. Clears the event queue
Which event is triggered when a web page finishes loading?
A). A. onload
B). B. onsubmit
C). C. onmouseover
D). D. onclick
Which method is used to attach an event listener to an HTML element in JavaScript?
A). A. appendEvent()
B). B. addEventListener()
C). C. attachEvent()
D). D. bindEvent()
What is the purpose of the removeEventListener() method in JavaScript?
A). A. To add event listeners to HTML elements
B). B. To detach event listeners from HTML elements
C). C. To prevent event propagation in event handling
D). D. To modify HTML content dynamically
Consider the following JavaScript code: document.addEventListener('keypress', function(event) { console.log('Key pressed:', event.key); }); What does this code do?
A). A. Adds a click event listener to the document
B). B. Adds a keypress event listener to the document
C). C. Removes a keypress event listener from the document
D). D. Checks if a key is pressed while hovering over an element
Which event occurs when a user submits an HTML form?
A). A. onsubmit
B). B. onmouseover
C). C. onkeydown
D). D. onclick
Which event is triggered when a user clicks on an HTML element?
A). A. onhover
B). B. onsubmit
C). C. onload
D). D. onclick