How to Make HTML Select Fields Required?

Validating User Input in HTML Select Fields with Required Attribute

Despite its presence in other HTML form elements, the required attribute is not natively supported by HTML select fields. However, there is a method to achieve this functionality.

Prerequisites:

• Valid HTML5 document type declaration (e.g., )
• Named input field within the select element (e.g., name="some_name")

Implementation:

To make a select field mandatory, ensure the following:

1. Empty First Value: The first option in the select list should have an empty value (e.g., ). This serves as a placeholder for empty selection.
2. Required Attribute: Add the required attribute to the select element (e.g., ).

Example:

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

Explanation:

According to HTML5 specifications, when the following conditions are met, the empty first value serves as a placeholder:

• The select element has a required attribute.
• The element does not have a multiple attribute.
• The display size is 1 (i.e., no SIZE attribute or SIZE="1").
• The value of the first option is an empty string (e.g., value="").

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