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
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
Which method is used to remove an event listener from an HTML element in JavaScript?
A). A. removeEventListener()
B). B. detachEvent()
C). C. removeEvent()
D). D. clearEventListener()
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.
Which event is triggered when a user clicks on an HTML element?
A). A. onhover
B). B. onsubmit
C). C. onload
D). D. onclick
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
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
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
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