Regular expression for validating phone number
When applied to a type, the model binding system requires values for all of the properties of that type.When you use a Nullable can be used to control the client-side validation error message.After model binding and validation are complete, you may want to repeat parts of it.
In MVC, validation happens on both the client and server. NET has abstracted validation into validation attributes.
However, some validation rules are specific to your business.
Your rules might not be common data validation techniques such as ensuring a field is required or that it conforms to a range of values.
It saves time they would otherwise spend waiting for a round trip to the server.
In business terms, even a few fractions of seconds multiplied hundreds of times each day adds up to be a lot of time, expense, and frustration.