Thearia-required attribute indicates that user input is required on the element before a form may be submitted.

Description

When a semantic HTML<input>,<select>, or<textarea> must have a value, it should have therequired attribute applied to it. The HTMLrequired attribute disables submitting the form unless the required form controls have valid values, while ensuring those navigating with the aid of assistive technologies understand which semantic form controls need valid content.

When form controls are created using non-semantic elements, such as a<div> with arole ofcheckbox, thearia-required attribute should be included, with a value oftrue, to indicate to assistive technologies that user input is required on the element for the form to be submittable. Thearia-required attribute can be used with HTML form elements; it is not limited to elements that have an ARIA role assigned.

Similar to the HTMLrequired attribute set on semantic HTML form controls, thearia-required attribute explicitly conveys to assistive technologies that the element is required before a form may be submitted. Therequired attribute on a semantic HTML form control will prevent the form control from being submitted if no value is present — providing native error messaging in some browsers if a required value is invalid when the user attempts to submit the form. Thearia-required attribute, like all ARIA states and properties, has no impact on element functionality. Functionality and behavior must be added in with JavaScript.

The CSS:required and:optional pseudoclasses match<input>,<select>, and<textarea> elements based on whether they are required or optional, respectively. When using non-semantic elements as form controls, you don't get this CSS pseudoclass selector benefit. You can, however, use attribute selectors if the attribute is present:[aria-required="true"] or[aria-required="false"].

If a form contains both required and optional form elements, the required elements should be indicated visually using a treatment that does not rely solely on color to convey meaning. Typically, descriptive text and/or an icon are used.

Examples

The attribute should be added to the form-control role. If the user needs to fill in an email addresstextbox, includearia-required="true" on the textbox.

<div>Email Address *</div><div  role="textbox"  contenteditable  aria-labelledby="tblabel"  aria-required="true" ></div>

In this example, JavaScript must be used to prevent the containing form from being submitted if the textbox has no content.

This could be written semantically, without the need for #"email1">Email Address (required)</label><input type="email" required />