HTML5
A vocabulary and associated APIs for HTML and XHTML
This is revision 1.5612.
This is revision 1.5612.
optgroup elementselect element.option elements.disabledlabelinterface HTMLOptGroupElement : HTMLElement {
attribute boolean disabled;
attribute DOMString label;
};
The optgroup element represents a group of
option elements with a common label.
The element's group of option elements consists of
the option elements that are children of the
optgroup element.
When showing option elements in select
elements, user agents should show the option elements
of such groups as being related to each other and separate from
other option elements.
The disabled attribute
is a boolean attribute and can be used to disable a group of
option elements together.
The label
attribute must be specified. Its value gives the name of the group,
for the purposes of the user interface. User
agents should use this attribute's value when labelling the group of
option elements in a select
element.
The disabled and label attributes must
reflect the respective content attributes of the same
name.
The following snippet shows how a set of lessons from three
courses could be offered in a select drop-down
widget:
<form action="courseselector.dll" method="get">
<p>Which course would you like to watch today?
<p><label>Course:
<select name="c">
<optgroup label="8.01 Physics I: Classical Mechanics">
<option value="8.01.1">Lecture 01: Powers of Ten
<option value="8.01.2">Lecture 02: 1D Kinematics
<option value="8.01.3">Lecture 03: Vectors
<optgroup label="8.02 Electricity and Magnestism">
<option value="8.02.1">Lecture 01: What holds our world together?
<option value="8.02.2">Lecture 02: Electric Field
<option value="8.02.3">Lecture 03: Electric Flux
<optgroup label="8.03 Physics III: Vibrations and Waves">
<option value="8.03.1">Lecture 01: Periodic Phenomenon
<option value="8.03.2">Lecture 02: Beats
<option value="8.03.3">Lecture 03: Forced Oscillations with Damping
</select>
</label>
<p><input type=submit value="▶ Play">
</form>