Server-side validation incorporates code validation into a form handler. NET application on the server that provides the functionality that your form needs for processing after a customer has submitted it.Because the code is stored on the server, server-side validation requires a roundtrip to the server.Note Front Page Server Extensions are a set of programs that provide access to special Front Page features, such as database processing, form processing, hit counters, and other built-in Front Page components that require server-side processing.You can provide custom validation for your forms in two ways: server-side validation and client-side validation.If you're working with arrays of checkboxes to submit data to a server-side script then you might already have some grey hairs from trying to figure out how to validate the input using Java Script.The problem is that, to have the data submitted in a 'nice' format to the server, the function returns an array containing all the selected checkbox values. In more complicated forms you will want to set conditions on the form that combine multiple elements.
Only when all conditions have been satisfied do we reach the command, in which case the form will be submitted.You'll see that the all validation scripts presented on this and subsequent pages adhere to the same basic format.Most modern browsers now support HTML5 Form Validation making it possible to validate form elements without (or before) any Java Script is triggered.When the form is submitted - either by hitting Enter or clicking on the Submit button - the (the 'value' of the field called 'input' belonging to the form). In a real-life situation you will most likely have more fields to check, and more complicated conditions, but the principle remains the same.Other form values are available using a similar syntax, although this becomes more complicated if you're using SELECT lists, checkboxes or radio buttons (see below for examples). All you need to do is extend the command is encountered, execution of the function is halted.