Define Validation Control in ASP.NET.
- The validation control is used to implement page level validity of data entered in the server controls.
- This check is done before the page is posted back to the server, thus avoid a round trip to the server.
- If the data does not pass validation, it will display an error message to the user.
- It is an important part of any web application.There are two types of validation:
1. Client side
2. Server side
- Validation controls are mostly used for implementing presentation logic, to validate user input data, data format, data type and data range.
- Client side validation is good, but we have to be dependent on the browser and scripting language support.
- Server validation will work always whether client validation is executed or not.Following are the six types of validation control:
|Sr. No.||Validation control||Description|
|1.||RequiredFieldValidation Control||It makes an input control a required field.|
|2.||CompareValidator Control||It compares the value of one input control to the value of another input control or to a fixed value.|
|3.||RangeValidator Control||It checks that the user enters a value that falls between two values.|
|4.||RegularExpressionValidator Control||It ensures that the value of an input control matches a specified pattern.|
|5.||CustomValidator Control||It allows you to write a method to handle the validation of the value entered.|
|6.||ValidationSummary||It displays a report of all validation errors occurred in a web page.|