Input Validation in ASP.NET

Input validation is very important for web application because an open input field can lead to successful hack attempts, system crashes, malicious data manipulation, data corruption, and notorious Denial of Service (DoS) situation. ASP.NET has five built-in validator controls to make life easier. A validator is a control that checks one input control for a specific type of error condition and displays a description of that problem. These controls improve performance besides simplifying validations.

• RequiredFieldValidation
• CompareValidator
• RangeValidator
• RegularExpressionValidator
• CustomValidator