ExampleGroup related options with <optgroup> tags: <select> <optgroup label="Group one"> <option value="element1">Element1</option> <option value="element2">Element2</option> </optgroup> <optgroup label="Group Two"> <option value="element3">Element3</option> <option value="element4">Element4</option> <option value="element5">Element5</option> </optgroup> </select> | Browser Support |
1. Definition and Usage
The <optgroup> is used to group related options in a drop-down list.
If you have a long list of options, groups of related options are easier to handle for a user.
2. Differences Between HTML and XHTML
None
3. Required Attributes
DTD indicates in which HTML 4.01/XHTML 1.0 DTD the attribute is allowed. S=Strict, T=Transitional, and F=Frameset.
| Attribute | Value | Description | DTD |
|---|---|---|---|
| label | text | Specifies a label for an option-group | STF |
4. Optional Attributes
| Attribute | Value | Description | DTD |
|---|---|---|---|
| disabled | disabled | Specifies that an option-group should be disabled | STF |
5. Standard Attributes
The <optgroup> tag supports the following standard attributes:
| Attribute | Value | Description | DTD |
|---|---|---|---|
| class | classname | Specifies a classname for an element | STF |
| dir | rtl ltr | Specifies the text direction for the content in an element | STF |
| id | id | Specifies a unique id for an element | STF |
| lang | language_code | Specifies a language code for the content in an element | STF |
| style | style_definition | Specifies an inline style for an element | STF |
| title | text | Specifies extra information about an element | STF |
| xml:lang | language_code | Specifies a language code for the content in an element, in XHTML documents | STF |
6. Event Attributes
The <optgroup> tag supports the following event attributes:
| Attribute | Value | Description | DTD |
|---|---|---|---|
| onclick | script | Script to be run on a mouse click | STF |
| ondblclick | script | Script to be run on a mouse double-click | STF |
| onmousedown | script | Script to be run when mouse button is pressed | STF |
| onmousemove | script | Script to be run when mouse pointer moves | STF |
| onmouseout | script | Script to be run when mouse pointer moves out of an element | STF |
| onmouseover | script | Script to be run when mouse pointer moves over an element | STF |
| onmouseup | script | Script to be run when mouse button is released | STF |
| onkeydown | script | Script to be run when a key is pressed | STF |
| onkeypress | script | Script to be run when a key is pressed and released | STF |
| onkeyup | script | Script to be run when a key is released | STF |
