Name
Radio — a graphical radio button
Availability
JavaScript 1.0; enhanced in JavaScript 1.1
Inherits from/Overrides
Inherits from Input, HTMLElement
Synopsis
The Radio button element is usually used in groups of mutually exclusive options that have the same name. To reference one Radio element within a group, use this syntax:
form.radio_name[j]form.radio_name.length
Properties
Radio inherits properties from Input and HTMLElement and defines or overrides the following:
-
checked A read/write boolean that is
trueif the radio button is checked orfalseotherwise. If you setcheckedtotrue, the radio button is selected, and the previously selected button is deselected. Note, however, that setting thecheckedproperty of a radio button tofalsehas no effect, because at least one button must always be selected; you cannot deselect a radio button except by selecting some other button. Note also that setting thecheckedproperty does not cause the Radio button element’sonclickevent handler to be invoked. If you want to invoke that event handler, you must do so explicitly.-
defaultChecked A boolean property that is
trueif the radio button is initially selected, but only if thecheckedattribute appears in the button’s HTML<input>tag. If this tag does not appear, the radio button is initially deselected, anddefaultCheckedisfalse.-
value A read/write string that specifies the text passed to the web server if the radio button is checked when the form is submitted. The initial value ...