How to Set HTML5 Required Attribute Dynamically in Javascript?

Setting HTML5 Required Attribute Dynamically in Javascript

Problem:

To ensure data accuracy, it's often necessary to mark form fields as required, prompting users to fill them out before submitting. While the required attribute can be defined in HTML markup, there are scenarios where setting it dynamically through Javascript is necessary.

Recommended Solution:

To correctly set the HTML5 required attribute in Javascript, use the following syntax:

<code class="javascript">element.required = true;</code>

Where:

• element represents the input field element for which you want to apply the required attribute.

Usage:

For example, to mark the text input field with the ID "edName" as required:

<code class="javascript">document.getElementById("edName").required = true;</code>

Underlying Mechanism:

The required attribute is a reflected boolean property. When you assign true to element.required, it ensures that the field is marked as required, triggering validation errors if left empty during form submission.

Important Note:

Unlike other HTML5 validation attributes that can be set using the setAttribute() method, setting the required attribute requires using the direct required property assignment due to its reflected nature.

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