ASP.Net Core MVC: Server Side Mobile Number (Cellphone Number) Validation using Data Annotations

Here Mudassar Khan has explained with an example, how to perform Mobile Number (Cellphone Number) TextBox validation i.e. exact Ten Numbers (Digits) validation on Server Side using Data Annotation in ASP.Net Core MVC. The Mobile Phone Number (Cellphone Number) validation will be performed using Regular Expression (Regex).