To stop users from submitting a form without filling out every required field simply add a
required attribute to the input element that they must fill to submit:
<form id="form"> <input type="text" name="full-name" placeholder="Full name" required /> <input type="text" name="email" placeholder="Email" required /> <input type="text" name="phone-number" placeholder="Phone number" /> <button id="button-submit-form" type="submit"> Submit Form </button> </form>
Both full name and email has the
required attribute in the code above.
Now if a user clicks on the Submit Form button without filling both required fields, they get the following popup warning: