You are designing a user input form that is part of an ASP.NET Web Forms application.
You need to ensure that users cannot attack the Web server by submitting invalid data.
Which approach should you recommend?
A.
Install a certificate on the Web server, and force all Web traffic to use SSL.
B.
Write an onSubmit JavaScript handler that validates all form input.
C.
Write an onSubmit JavaScript handler that URL-encodes all data that is passed to the server.
D.
Write an OnClick method for the Submit button that rejects form submissions that contain invalid data.
Explanation:
on the client side only onclick method can be used for validate submited form.