C# Model Required field attribute

ValueRequiredAttribute

 public class ValidationHelper : IValidationHelper
    {
        public  bool AllPropertiesAreValid(object obj)
        {
            if (obj == null)
            {
                return false;
            }
                
            return obj.GetType().GetProperties().All(p =>
            {
                var attrib = p.GetCustomAttributes(typeof(ValueRequiredAttribute), true)
                                 .FirstOrDefault() as ValueRequiredAttribute ?? new ValueRequiredAttribute();

                return attrib.Validate(p.GetValue(obj));
            });
        }
    }

    [AttributeUsage(AttributeTargets.Property)]
    public class ValueRequiredAttribute : Attribute
    {
        public bool Validate<T>(T value)
        {
            if (Equals(value, default(T)))
            {
                return false;
            }

            return true;
        }
    }