VALIDATION CONTROL: INTRODUCTION
ASP.NET provides six validations controls that can be used to validate the data on a web form and validate the user input data to ensure that useless, unauthenticated or contradictory data does not get stored.
This validation controls can be used with HTML and Web Server controls. Six validation controls are available with ASP.NET as of now, they are as follows –
The RequiredFieldValidator Control – Ensures that the user does not skip a mandatory entry field.
The CompareValidator Control – Compares one controls value with another controls value, constants and data type using a comparison operator (equals, greater than, less than, and so on).
The RangeValidator Control – Checks the user’s input is in a given range (eg: numbers or characters).
The RegularExpressionValidator Control – Checks that the user’s entry matches a pattern defined by a regular expression.
The CustomValidator Control – Checks the user’s entry using custom-coded validation logic.
The ValidationSummary Control – Displays a summary of all validation errors inline on a web page, in a message box, or both.