How to use validation in the form?

Form Validation in HTML and JavaScript

In HTML, form validation is implemented using CSS pseudo-classes ": invalid" and ": valid" to <input>, <select>, and <textarea> elements. On the other hand, JavaScript form validation verifies the user's input before the form is submitted to ensure accuracy. This process helps identify errors and enhances the user experience. See the example below for further clarification:

JavaScript Form Validation Example

function validateTheForm() {

  let i = document.forms["myForm"]["fname"].value;

  if (i == "") {

    alert("Name must be filled out");

    return false;

  }

}

This isn't meant to highlight the difference between HTML form validation and JavaScript form validation; it's simply a basic example with a simple definition to help you understand how to use form validation code. So, don’t get confused.