HTML optgroup tag
Note: If you don't know what a tag is and/or how you must use it we recommend you to read our HTML tags and attributes tutorial that you can find in our HTML tutorials section.
The
HTML optgroup tag allows authors to group options in a select list (
HTML select tag).
The "id" attribute assigns an identifier to the associated element. This identifier must be unique in the document and can be used to refer to that element.
Example:
Code begin
<p id="paragraph1">This is the first paragraph named as paragraph1. To dynamically change its properties use this identifier.</p>
Code end
The "class" attribute assigns a class name (or a list of class names separated by spaces) to the container element. It's used with style sheets and tells the browser the class to which the element is associated with. A class gives visual attributes to elements.
Example:
Code begin
<p class="references">This article is based on the book "Wind in the trees" by Jhon L. Brooks</p>
<p class="references important">This article is based on the book "Wind in the trees" by Jhon L. Brooks... and is more important than the one before.</p>
Code end
Defines a visual style of this element. Is a better practice to define styles attributes in external style sheets grouping them in classes. Attributes in the "style" parameter must preserve this order "name : value" and be separated by a semi-colon.
If you're writing
XHTML code it's recommended not to use this attribute and try style sheet classes (with the "class" attribute).
Example:
Code begin
<p style="color: #0000FF; font-size: 12pt">This is a paragraph with a defined style</p>
<p>And this is another text without style.</p>
Code end
Indicates a title for the element. Used to give a short description about the element that is usually shown as a "tool tip" when the user put the mouse pointer over the element.
Example:
| Code |
View |
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<a title="HTMLQuick.com" href="http://www.htmlquick.com">HTML code</a> |
HTML code |
Specifies the language of an element's content. The default value in "unknown".
When writing
XHTML code the syntax "xml:lang" represents a preferred alternative in XHTML 1.0 and a replacement in XHTML 1.1 (e.g., xml:lang="en").
Example:
Code begin
<p lang="en">This is a paragraph in english.</p>
<p lang="es">Este es un párrafo en español.</p>
Code end
dir
Specifies the text direction of the element's contents and attribute values, as well as tables directionality. It has two possible values that are case insensitive:
- RTL: Right to left.
- LTR: Left to right.
Example:
Code begin
<q lang="he" dir="rtl">...a Hebrew quotation...</q>Code end
disabled
When this attribute is set, the control is disabled, this means than it cannot get the focus, it's value cannot be changed and it will not be submitted with the form. Dependign on the browser, disabled element may be shown different.
Example:
| Code |
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<form action="example.php">
<div>
<input name="firstbutton" type="button" value="This is not disabled" /><br /><br />
<input name="secondbutton" type="button" value="This is disabled" disabled="disabled" /><br /><br />
<input name="secondtext" type="text" value="This is not disabled" /><br /><br />
<input name="firsttext" type="text" value="This is disabled" disabled="disabled" />
</div>
</form> |
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Specifies a label for the option group. This text will be shown as a title for the group.
- onclick
- ondblclick
- onmousedown
- onmouseup
- onmouseover
- onmousemove
- onmouseout
- onkeypress
- onkeydown
- onkeyup
See complete list and information about
events in HTML
Common example.
| Code |
View |
<form action="example.php">
<div>
<select>
<optgroup label="Server-side languages">
<option>PHP</option>
<option>ASP</option>
</optgroup>
<optgroup label="Client-side languages">
<option>JavaScript</option>
<option>VBScript</option>
</optgroup>
</select>
</div>
</form> |
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