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 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 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 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
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
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: 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
What is the purpose of the onclick attribute in HTML elements?
A). A. To define styles for HTML elements
B). B. To attach event listeners for mouse clicks
C). C. To insert JavaScript code directly into HTML
D). D. To create animations for HTML elements
What is the purpose of an event in JavaScript?
A). A. To add styles to HTML elements
B). B. To handle user interactions and browser actions
C). C. To define function names
D). D. To create animations on web pages