Validating forms with
If correct, the application allows the data to be submitted to the server and (usually) saved in a database; if not, it gives you error messages to explain what you've done wrong (provided you've done it right).
Form validation can be implemented in a number of different ways.
For example, if you have a text box that must contain a postal code, you can perform the validation in the following ways: The Validating event is supplied an object of type Cancel Event Args.
There are three main reasons: In the real world, developers tend to use a combination of client-side and server-side validation, to be on the safe side.When you use data binding, the data in your control is synchronized with the data source during execution of the Validating event.If you cancel the Validating event, the data will not be synchronized with the data source.Form validation helps us achieve these goals — this article tells you what you need to know.This is called form validation — when you enter data, the web application checks it to see if it is correct.
In this case, to perform validation in the Validated event, change the control's Data Source Update Mode property (under (Databindings)\(Advanced)) from On Validation to Never, and add So when does a control's data get validated? You can use either implicit or explicit validation, depending on the needs of your application.