A. Add a CompareValidator control to the Web Form. Set its ControlToValidate property to txtDate. Set its Type property to Date. Set its Operator property to DataTypeCheck.
B. Add a RangeValidator control to the Web Form. Set its ControlToValidate property to txtDate. Set its Type property to Date. Set its MinimumValue property to 01/01/1900 and its MaximumValue to the current date.
C. Add a CustomValidator control to the Web Form. Set its ControlToValidate property to txtDate. Write a function in the partial class that verifies the values as dates and returns a Boolean variable. Set the CustomValidators ClientValidationFunction to the name of your function.
D. Add a RegularExpressionValidator control to the Web Form. Set its ControlToValidate property to txtDate. Set the ValidationExpression property to ensure that the users input follows the format of nn-nn-nnnn, where n represents a number from 0 through 9.