Why And How To Do Javascript Validation?

[THE ADMIN]

JAVASCRIPT VALIDATION (WHY & HOW)

In the web to add interactivity forms play a major role. To get an input from the user and then to process a request based on the input provided, forms are used. In most of the webpages you would see a form to get some data from you. That can be a Login Form, Registration Form, Comment Form, Mail to Admin form or some special purpose forms which are famous nowadays such as a forms providing Mobile Recharge by requesting Provider Name, Mobile Number, Amount of Recharge, Bank Card Number, Pin Number, etc. You can remember now a form for Booking Train tickets in IRCTC too. Those forms consists of fields, such as Textboxes, Drop Down List boxes, Radio Buttons, Check Boxes, Labels, Submit Buttons and so on. The data is obtained from the users through these fields. Given below is a screenshot of a typical Gmail Registration Page Fig (a) Before Validation Fig (b) After Validation.