It is important to validate the form submitted by the user because it can have inappropriate values. So, validation is a must to authenticate the user. JavaScript provides the facility to validate the form on the client-side so data processing will be faster than server-side validation. Most web developers prefer JavaScript form validation.
Through JavaScript, we can validate name, password, email, date, mobile numbers and more fields.
The data entered into a form needs to be in the right format and certain fields need to be filled in order to effectively use the submitted form. Username, password, contact information are some details that are mandatory in forms and thus need to be provided by the user.
Basic Syntax:
function validateForm() {
let x = document.forms["myForm"]["fname"].value;
if (x == "") {
alert("Name must be filled out");
return false;
}
}