How to enter Date in a given format in a TextBox in ASP.NET?

In ASP.NET, date can be validated easily by using RegularExpressionValidator. Suppose that you want your user to enter the date in (DD-MM-YYYY) format in a TextBox named Date_of_Birth. To do so, you just need to set the following RegularExpressionValidator properties:

ID	Date_Validator
ControlToValidate	Date_of_Birth
ErrorMessage	Please fill the date in correct format
ValidationExpression	^(\d{2})\-(\d{2})\-(\d{4})$

If you want your user to enter the date in (DD/MM/YYYY) format, then ValidationExpression property will be as follows:

ValidationExpression

^(\d{2})\/(\d{2})\/(\d{4})$

If you want your user to enter the date in (D-M-YY) format, then ValidationExpression property will be as follows:

ValidationExpression

^(\d{1,2})\-(\d{1,2})\-(\d{2})$

(Note: You can change Error Messages, Control Names and Formats according to your project requirements.)