October 2010
Intermediate to advanced
1920 pages
73h 55m
English
Content preview from ASP.NET 4 Unleashed
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Validation Controls and JavaScript
By default, the validation controls perform validation on both the client (the browser) and the server. The validation controls use client-side JavaScript. This is great from a user experience perspective because you get immediate feedback whenever you enter an invalid value into a form field.
Note
The RequiredFieldValidator does not perform client-side validation until after you attempt to submit a form at least once or you enter and remove data in a form field.
Almost all desktop browsers support client-side JavaScript. Supported browsers include Internet Explorer, Firefox, Chrome, Safari, and Opera. It is becoming more common to browse the web on mobile devices such as cell phones. Many of these mobile ...