Which event is triggered when a web page finishes loading?
A). A. onload
B). B. onsubmit
C). C. onmouseover
D). D. onclick
Consider the following HTML code: Which JavaScript code adds a click event listener to the button?
A). A. document.getElementById('myButton').onclick = function() { alert('Button clicked'); };
B). B. document.getElementById('myButton').addEventListener('click', function() { alert('Button clicked'); });
C). C. document.getElementById('myButton').click(function() { alert('Button clicked'); });
D). D. document.getElementById('myButton').on('click', function() { alert('Button clicked'); });
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 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; }
What is the purpose of the onmouseover event in HTML?
A). A. To detect when an element is hovered over
B). B. To track changes in form inputs
C). C. To determine when an element is loaded
D). D. To handle form submissions
What is the primary purpose of JavaScript functions?
A). A. To style web pages
B). B. To provide structure to HTML elements
C). C. To create reusable code blocks
D). D. To define CSS styles for HTML
Which event is triggered when a user clicks on an HTML element?
A). A. onhover
B). B. onsubmit
C). C. onload
D). D. onclick
How can you attach multiple event listeners to the same HTML element in JavaScript without overwriting existing ones?
A). A. By using the attachEvent() method
B). B. By using the addEventListener() method with the replace parameter
C). C. By assigning multiple functions directly to the element's event attributes (e.g., onclick, onmouseover)
D). D. By using the addEventListener() method multiple times for the same event
Which statement accurately describes JavaScript event bubbling?
A). A. It refers to the downward propagation of events from parent elements to child elements.
B). B. It refers to the upward propagation of events from child elements to parent elements.
C). C. It refers to the simultaneous firing of multiple events on the same element.
D). D. It refers to the automatic removal of event listeners after an event is triggered.
What is the purpose of parameters in a JavaScript function?
A). A. To return a value from the function
B). B. To define the function's name
C). C. To store variables within the function
D). D. To accept inputs into the function