Blog

In JavaScript, if the variable flower has been assigned the value “bluebell”, the expression typeof(flower); will return _____.

When you register to use third-party services, you should expect these services to provide APIs organized by endpoints, which are essentially the URLs to which requests are made and that provide the points of contact between the client device and the service’s resources.

To extract the date and approximate time (in hours and minutes) from a JavaScript Date object, you can apply the get(Month), getDate(), getFullYear(), getHours(), and getMinutes() methods to that object.

Suppose you are examining the script for the orderForm web form, whose submit button has the id submitButton. The form includes option buttons for choosing a pizza sauce flavor. The following JavaScript code included in the script will check for a sauce selection when the user clicks the submit button and display a custom error message if a sauce was not chosen.​let submitButton = document.getElementById(“submitButton”);submitButton.addEventListener(“click”, validateSauce);function validateSauce() {   let sauce = document.forms.orderForm.elements.sauceType[0];   if (sauce.validity.valueMissing) {      sauce.setCustomValidity(“”);   } else {      sauce.setCustomValidity(“Choose a sauce, please”);   }}

In JavaScript, you can use the apply() method to borrow a method from one object class and use it on objects of a different class without defining the second class as an instance of the first class.

Which statement regarding error handling for the following JavaScript statement is correct?fetch(“bullfrogStory.html”).then(response => response.text()).then(text => story.innerHTML = text).catch(story.innerHTML = “Error loading story.”);

What does the following JavaScript code accomplish?let surveyForm = window.open(“”);let mainHeading = document.createElement(“h1”);mainHeading.textContent = “Your Experience”;surveyForm.document.body.appendChild(mainHeading);

The following JavaScript code will display the message “Please enter your name!” instead of the browser’s native error message when executed in response to a user trying to submit a web form without entering text in the lastName field, which has the required attribute. let lastName = document.getElementById(“lastName”);lastName.setCustomValidity(“Please enter your name!”);

Suppose you have created a chooseActivity promise object in your JavaScript program. You want to initiate the promise and pass the resulting value to another function if chooseActivity resolves successfully. What code should you write to do this?

The JavaScript window.alert() method makes a dialog box appear that contains the literal string passed to it plus an OK button that can be clicked to close the box.