C# Online Compiler | .NET Fiddle

using System;
using AutoMapper;
using System.ComponentModel;

public class Person
{
	public string Name { get; set; }
	public int Age { get; set; }
	[NoMap]
	public string Address { get; set; }
	[NoMap]
	public string Email { get; set; }
	
}

public class PersonVM
{
	
	public string Name { get; set; }
	public int Age { get; set; }
	public string Address { get; set; }
	public string Email { get; set; }
	
}


public class NoMapAttribute : System.Attribute
{
    
	
}

public static class IgnoreNoMapExtensions
{
	public static IMappingExpression<TSource, TDestination> IgnoreNoMap<TSource, TDestination>(
               this IMappingExpression<TSource, TDestination> expression)
    {
        var sourceType = typeof(TSource);

        foreach (var property in sourceType.GetProperties())
        {
            PropertyDescriptor descriptor = TypeDescriptor.GetProperties(sourceType)[property.Name];
            NoMapAttribute attribute = (NoMapAttribute) descriptor.Attributes[typeof(NoMapAttribute)];
			
            if(attribute != null)
                expression.ForMember(property.Name, opt => opt.Ignore());
        }
        return expression;
    }
}

public class Program
{
	public static void Main()		
	{
		
		var config = new MapperConfiguration(cfg => { 
			cfg.CreateMap<Person, PersonVM>().IgnoreNoMap();
										 
		});
		
		IMapper mapper = config.CreateMapper();
		
				
		var person = new Person { Name="test", Age=10, Email = "test@test.com", Address="Test Address" };
		
		var personVM = mapper.Map<PersonVM>(person);
		
	    Console.WriteLine("\nperson.Name : {0} \nperson.Age : {1} \nperson.Address : {2} \nperson.Email : {3}", person.Name, person.Age, person.Email, person.Address);
		Console.WriteLine("\npersonVM.Name : {0} \npersonVM.Age : {1} \nperson.Address : {2} \nperson.Email : {3}", personVM.Name, personVM.Age, personVM.Email, personVM.Address);
	}
}

        Console.WriteLine("\npersonVM.Name : {0} \npersonVM.Age : {1} \nperson.Address : {2} \nperson.Email : {3}", personVM.Name, personVM.Age, personVM.Email, personVM.Address);
 
using System;
using AutoMapper;
using System.ComponentModel;
​
public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
    [NoMap]
    public string Address { get; set; }
    [NoMap]
    public string Email { get; set; }
    
}
​
public class PersonVM
{
    
    public string Name { get; set; }
    public int Age { get; set; }
    public string Address { get; set; }
    public string Email { get; set; }
    
}