DataAnnotations “NotRequired” attribute

Question

I\'ve a model kind of complicated.

I have my UserViewModel which has several properties and two of them are HomePhone and WorkPhone

Answer 1

I've been using this amazing nuget that does dynamic annotations: ExpressiveAnnotations

It allows you to do things that weren't possible before such as

[AssertThat("ReturnDate >= Today()")]
public DateTime? ReturnDate { get; set; }

or even

public bool GoAbroad { get; set; }
[RequiredIf("GoAbroad == true")]
public string PassportNumber { get; set; }

Update: Compile annotations in a unit test to ensure no errors exist

As mentioned by @diego this might be intimidating to write code in a string, but the following is what I use to Unit Test all validations looking for compilation errors.

namespace UnitTest
{
    public static class ExpressiveAnnotationTestHelpers
    {
        public static IEnumerable CompileExpressiveAttributes(this Type type)
        {
            var properties = type.GetProperties()
                .Where(p => Attribute.IsDefined(p, typeof(ExpressiveAttribute)));
            var attributes = new List();
            foreach (var prop in properties)
            {
                var attribs = prop.GetCustomAttributes().ToList();
                attribs.ForEach(x => x.Compile(prop.DeclaringType));
                attributes.AddRange(attribs);
            }
            return attributes;
        }
    }
    [TestClass]
    public class ExpressiveAnnotationTests
    {
        [TestMethod]
        public void CompileAnnotationsTest()
        {
            // ... or for all assemblies within current domain:
            var compiled = Assembly.Load("NamespaceOfEntitiesWithExpressiveAnnotations").GetTypes()
                .SelectMany(t => t.CompileExpressiveAttributes()).ToList();

            Console.WriteLine($"Total entities using Expressive Annotations: {compiled.Count}");

            foreach (var compileItem in compiled)
            {
                Console.WriteLine($"Expression: {compileItem.Expression}");
            }

            Assert.IsTrue(compiled.Count > 0);
        }


    }
}