Validating custom control attributes
The malicious user can then submit the modified script to the Web server with results that are different than what you, the developer, intended.
The alternative to processing data validation on the user's computer is to process it on the Web server.
If you choose to support validation on the user's computer, performance will increase slightly.
However, to reiterate, validation will always be performed on the Web server in order to offer validation to Web browsers that do not support the client-side scripting as well as protect against the possibility of modified validation scripts.
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.Shannon Horn is the co-founder and chief software architect of Web Geniuses Corporation ( Hence, many times validation was not performed in a uniform manner, complex validation was difficult to implement, and Web servers were vulnerable to validation scripts being modified by malicious users.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 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. NET, data validation was performed through scripts using either Java Script or VBScript.