Web control validation may be defined using one or more declarations that are
included in an ASP+ file by the web page author. The declarations specify server-side
objects that validate the input data received in the web page and provide error
handling in the event of a validation failure error. Validation declaration parameters
specify the validation criteria against which the input data is validated. Example
validation operations involve regular expressions, required fields, data comparison,
range comparison and custom validation. Validation parameters can also specify-
either server-side validation or client-side validation, depending on the client
browser's capabilities. In a server-side scenario, a server-side validation object
processes the input data received in an HTTP request from the client. In a client-side
scenario, a server-side validation object renders the appropriate client-side code
to validate the input data without a round trip between the client and the server.
