Data collection on the Internet is one of its most important features, so you must make sure that the data you collect has value and meaning.You ensure this by eliminating any chance that the information collected does not abide by the rules you outline. NET don't know the difference between client-side and server-side validation.Nothing is more annoying to a user who is on a dial-up connection than clicking the Submit button on the form and then waiting for 20 seconds to find out that they didn't enter their password correctly.The other option for form validation is to put some client-side Java Script or VBScript at the top of the ASP page that checks if the information in the fields is correct.This piece of code determines only whether the user entered anything at all in all five fields within the form.It does not determine whether the user entered an actual e-mail address within the e-mail address text box, whether the user entered a number between two given numbers, or whether the password and the confirm password text boxes match.When you used server-side validation with ASP 3.0, if something the user entered was wrong, you could repost the form and ask the user to correct the information in that particular field of the form.
This takes a lot of resources and makes for a slower-paced form for the user.
This takes care of the problem of making unnecessary trips to the server, but it requires another language to learn and manage.
Java Script is a great language, but takes a lot of time to master, and there are always problems getting your Java Script code to work on different browsers.
Some sites on the Internet don't carry this inputted information back to the form page, and the user is then required to enter all the information into the form a second time.
Obviously, this may cause people to leave your site for another.