Self validating web forms
If the linked control has a value entered into it, data validation will succeed.
Alternatively, if the linked control is empty, data validation will fail.
In the snippet above I've declared a textbox with an ID attribute called txt Name.
The Required Field Validator linked to it has an ID attribute called rfv Name and I've included some of the most commonly used attributes.
NET and Web Services Solutions conference produced by PRO. He has also worked with large corporate clients including Microsoft, Universal Studios, MGM Studios, Monster.com/Flip Dog.com, Intel, Polygram Pictures, Prudential, Micro Accounting Systems, Sky Harbor International Airport, and Southern Automated Systems on projects using Microsoft technologies such as Visual Fox Pro, Visual Studio. Most applications perform their data validation on the user's local computer.
He is a published author on several subjects including XML, the migration from Visual Basic 6 to VB. In this scenario, if an error occurs while performing validation on the user's computer, the application can directly display the error message on the page that the user is viewing without the page making a round trip to the Web server and then back to the user.
He is a Microsoft Certified Application Developer (MCAD), Microsoft Certified Solution Developer (MCSD) and a Microsoft Certified Trainer (MCT) who has been developing Microsoft Windows and Web-based solutions as well as training for over 12 years. Shannon lives in Glendale, AZ, and is married with two daughters and a son. Validating the information entered by users is an essential part of developing a professional Web-based user interface.
He has been a featured speaker at many industry events including Microsoft Dev Days and the ASP. Shannon speaks and trains for companies such as App Dev ( and Learn It ( and has been a featured speaker in training videos with Learn Key. Data validation over the Web is performed in one of two locations: on the user's computer, or on the Web server.
All of the data validation controls are displayed in the toolbox when ASP.
Users with harmful intent may easily modify the validation script because it is contained in the source of the page that is sent to the user's computer.
The malicious user can then submit the modified script to the Web server with results that are different than what you, the developer, intended.
For instance, since the validation occurs on the Web server, your application must post the Web page that the user is viewing back to the Web server for validation to occur.
This decreases performance since the page must make a round trip to the Web server and back to the user's computer if data validation fails.