Chapter 6

Question 1

Which attribute enhances usability in modern browsers?

Answer 1

placeholder

Question 2

Which type value for the input element triggers validation in modern browsers?

Answer 2

number

Question 3

document.getElementsByTagName(“form”)[0], you could use the code

Answer 3

document.forms[0]

Question 4

Use of the ____ attribute of the form element is not allowed in the strict DTD for XHTML.

Answer 4

name

Question 5

Many aspects of the way browsers present browser-based validation feedback are customizable through the properties and methods of the​ ____.

Answer 5

constraint validation API

Question 6

In modern browsers, which attribute of an input element prevents the form from being submitted if the field is left blank?

Answer 6

required

Question 7

Displays a validation error in a modern browser

Answer 7

bubble

Question 8

​Reduce the likelihood of user errors when completing a form

Answer 8

assistive functions

Question 9

Enables customization of validation feedback in modern browsers

Answer 9

constraint validation API

Question 10

Persistence required for a user to accomplish a goal

Answer 10

​friction

Question 11

Determines whether a value is not a number

Answer 11

isNaN() function

Question 12

Checking that information provided by users conforms to rules

Answer 12

validation

Question 13

Provides guidance about what data should be entered in a text box

Answer 13

placeholder

Question 14

If all its properties are false, then its value is true

Answer 14

validity object

Question 15

Stops a form from being submitted when the submit event is triggered

Answer 15

preventDefault()

Question 16

Indicates that a form element must have a value

Answer 16

required

Question 17

The ____ event fires when a form is submitted.

Answer 17

submit

Question 18

For any fields that require numeric values, you can use JavaScript’s built-in ____ function to determine whether a user actually entered a number.

Answer 18

isNaN()

Question 19

Which form element is useful for limiting user options to a set of choices?

Answer 19

​selection list

Question 20

You can use the CSS ____ pseudo-classes to change the properties of form elements based on their validity status.

Answer 20

invalid and :valid

Question 21

You create an empty document fragment using the ____ method.​

Answer 21

​createDocumentFragment()

Question 22

To check a group of fields and trigger an error message if any of them is empty, you use a(n) ____ statement.

Answer 22

​loop

Question 23

When a control’s value is found to be invalid during constraint validation, the ____ event is triggered.

Answer 23

invalid

Question 24

Which attribute toggles off validation of a form when added to the opening tag?

Answer 24

novalidate

Question 25

To display no default value on a selection list, you set its ____ property to -1

Answer 25

selectedIndex

Question 26

What element property would you use when copying the contents of one text field to another text field?​

Answer 26

value

Question 27

You use the ____ method on an object to block the action normally associated with an event.​

Answer 27

​preventDefault()

Question 28

To check if an option button is selected, you access the value of its ____ property.

Answer 28

checked

Question 29

In general, modern browsers display validation feedback after the ____ event is triggered by a form.​

Answer 29

submit

Question 30

Validation errors found by modern browsers are reported in​ ____.

Answer 30

bubbles