How to Enforce Selection in HTML `` Fields with the `required` Attribute?

HTML Field Validation with required Attribute

Despite the lack of explicit required attribute support for fields in HTML, it's possible to enforce selection using this attribute with some specific HTML structure.

The requirement involves having the first value in the field be empty. By default, fields with empty first values will be treated as optional. However, by setting required on the field, it becomes mandatory to make a selection.

Here's an example of how to use it:

<code class="html"><select name="somename" required>
    <option value="">Please select</option>
    <option value="one">One</option>
</select></code>

According to the HTML5 specification, this structure satisfies the criteria for mandatory selection:

• required attribute is specified.
• The field does not have multiple attribute specified (indicating it's not for multiple selections).
• The display size is assumed to be 1 (since no size attribute is specified).
• The first option element has an empty value (in this case, "Please select").
• The first option element is a direct child of the element (not part of an optgroup).

By adhering to these conditions, the required attribute becomes functional for fields, ensuring that the user makes a selection before submitting the form.

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