Validation Controls in ASP.NET

Type of validation Control to use
Description

Required entry RequiredFieldValidator Ensures that the user does not skip an entry.

Comparison to a value CompareValidator Compares a user's entry against a constant value, or against a property value of another control, using a comparison operator (less than, equal, greater than, and so on).

Range checking RangeValidator Checks that a user's entry is between specified lower and upper boundaries. You can check ranges within pairs of numbers, alphabetic characters, and dates.

Pattern matching RegularExpressionValidator Checks that the entry matches a pattern defined by a regular expression. This type of validation allows you to check for predictable sequences of characters, such as those in social security numbers, e-mail addresses, telephone numbers, postal codes, and so on.
User-defined CustomValidator Checks the user's entry using validation logic that you write yourself. This type of validation allows you to check for values derived at run time.