How to Set the Required Field Attribute Dynamically with Javascript?

Assigning the Required Attribute in Javascript

In web development, setting form field validation attributes dynamically through Javascript can enhance user experience. One such attribute is the "required" attribute, which ensures that a user input is essential before submitting a form. By setting the attribute in Javascript, you can provide a more intuitive and user-friendly form experience.

Defining the Required Attribute

The HTML5 required attribute is a Boolean attribute, meaning it can be either true or false. When an element has the required attribute set to true, it indicates that the element's value is mandatory and must be filled in before the form can be submitted.

Setting the Required Attribute in Javascript

The recommended W3C HTML5 syntax for setting boolean attributes is through the attributes property, as shown below:

document.getElementById("edName").attributes["required"] = "";

However, in this case, the submission still occurs without validation. This is because the correct method to set the required attribute in Javascript is through the reflected property:

element.required = true;

The element variable represents the actual input DOM element you want to make required. For example:

document.getElementById("edName").required = true;

False Value for Boolean Attributes

To set the required attribute to false, removing it entirely from the element is necessary:

element.removeAttribute("required");

Checking the Value of the Attribute

When the required attribute is defined in the markup using , the attribute's value is neither an empty string nor its canonical name. Instead, it becomes an attribute object. To get the value of the attribute, look at its value property. However, for boolean attributes, the value is not relevant; the attribute's presence (true) or absence (false) determines its state.

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