Rollback nothing but it is like undo, we will retrive the last changed record

Two ways you can achieve this.1) You can use javaScript to validate the data.2) You can use Validation Controls. (One for Client Side Validation One for Server Side Validation)Even though Validation c...

Because the server side validation creates a dynamic javascript to validate the control at client side. You can do it without useing validation cotrol and by writing the dynamic javascript.