Handling Events - JavaScript by Example - page 483

the form, such as a checkbox, radio button, or text field. By naming each of the forms
and its respective elements, it is much easier to work with them in JavaScript. (See Chap-
ter 11 for a complete discussion of the forms[] array.) There are a number of events asso-
ciated with the form's elements. Many of them were also covered in Chapter 11. They
are listed in Table 13.6.

Table 13.6 Event Handlers for the Form's Elements

Object Event Handler

button onClick, onBlur, onFocus

checkbox onClick, onBlur, onFocus

FileUpLoad onClick, onBlur, onFocus

hidden none

password onBlur, onFocus, onSelect

radio onClick, onBlur, onFocus

reset onReset

select onFocus, onBlur, onChange

submit onSubmit

text onClick, onBlur, onFocus, onChange

textarea onClick, onBlur, onFocus, onChange

13.6.1 Buttons

One of the most common GUI form elements is the button. The button object has no
default action and is normally used to trigger an event such as the onClick event. HTML
4 allows you to create a <button> tag without the <input> tag. 3 There are several buttons
associated with a form; the buttons are called:

• submit

• reset

• button

If an event handler, such as onSubmit or onChange is an attribute of a form tag, then
the event occurs when the user clicks one of the buttons associated with the form object.
Form event handlers are listed in Table 13.7.

3. The <button> </button> tags give greater flexibility to the appearance of the button by allowing HTML con-
tent to be displayed instead of plain text that is assigned to the value attribute of a button created using
the <input type="button">.