CSS - :required

The :required CSS pseudo-class represents any <input> element that has the required attribute set on it. This allows forms to easily indicate which fields must have valid data before the form can be submitted.

Example

 

See :invalid for an example.

Syntax  

CSS
:required <a href="css/value_definition_syntax#curly_braces_(.7b_.7d)" title="Curly braces">{</a> <var>style properties</var> <a href="css/value_definition_syntax#curly_braces_(.7b_.7d)" title="Curly braces">}</a>

Description  

The :required CSS pseudo-class represents any <input> element that has the required attribute set on it. This allows forms to easily indicate which fields must have valid data before the form can be submitted.

The :optional pseudo-class may be used to provide an appearance for optional form fields.

Browser Compatibility  

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 10.0 4.0 (2) 10 10.0 5.0
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? 4.0 (2) No support 10.0 5.0

See Also  

Specifications  

Specification Status Comment
WHATWG HTML Living Standard
The definition of ':required' in that specification.
Living Standard No change.
HTML5
The definition of ':required' in that specification.
Recommendation Defines the semantic regarding HTML and constraint validation.
Selectors Level 4
The definition of ':required' in that specification.
Working Draft No change.
CSS Basic User Interface Module Level 3
The definition of ':required' in that specification.
Candidate Recommendation Defines the pseudo-class, but not the associated semantic.

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/css/:required

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