Web Front-endHTML TutorialWhat does the html optgroup tag mean? Analysis of usage and attribute examples of html optgroup tag
html What does the optgroup label mean? Regarding the usage and attribute instance analysis of the html optgroup tag, this article introduces the definition and attribute examples of the html optgroup tag, as well as the usage of the html optgroup tag
html optgroup tag Definition and usage:
The optgroup element is used to group options. When you work with a long list of options, grouping related options can make things easier.
HTML
Group related options together through the
<select>
<optgroup label="Swedish Cars">
<option value ="volvo">Volvo</option>
<option value ="saab">Saab</option>
</optgroup>
<optgroup label="German Cars">
<option value ="mercedes">Mercedes</option>
<option value ="audi">Audi</option>
</optgroup>
</select>Required attributes of the html optgroup label:
label: text: Specifies a description for the option group. (Example above)
html Optional attributes of the optgroup tag:
disabled: disabled: Specifies that the option group is disabled.
HTML
The disabled attribute definition of the optgroup tag:
The disabled attribute stipulates that it is disabled This option group. Disabled option groups are neither available nor clickable.
You can set the disabled attribute to restore the user's use of the option group until certain conditions are met (such as selecting a check box). You can then use JavaScript to clear the disabled attribute so that the option group becomes available.
Disabled attribute example of optgroup tag
A disabled option group:
##
<select>
<optgroup label="German Cars" disabled="disabled">
<option value="mercedes">Mercedes</option>
<option value="audi">Audi</option>
</optgroup>
</select>
html The usage of the optgroup tag is grouped, read-only and displayed in a tree style:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>optgroup</title>
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="this is my page">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
</head>
<body>
<select>
<optgroup label="Java">
<option value="jsp Servlet">jsp Servlet</option>
<option value="javaEE">javaEE</option>
</optgroup>
<optgroup label=".Net">
<option value="aspx">aspx</option>
<option value="C#">C#</option>
</optgroup>
</select>
</body>
</html>
Browser support
All major browsers support theThe above is the detailed content of What does the html optgroup tag mean? Analysis of usage and attribute examples of html optgroup tag. For more information, please follow other related articles on the PHP Chinese website!
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