This is the regx which can be used to validate UAE contact numbers in your developments.
In C# Use as below in your models
[RegularExpression("^(?:\\+971|00971|0)?(?:50|51|52|54|55|56|58|2|3|4|6|7|9)\\d{7}$", ErrorMessage = "Enter Valid UAE Numbers")]
public string Mobile { get; set; }
Verify and test this regx online : https://regexr.com/47qlv
In other designs you can use this
^(?:\+971|00971|0)?(?:50|51|52|54|55|56|58|2|3|4|6|7|9)\d{7}$