title: How to validate a List of Guid using FluentValidation
body: <p>I am trying to validate a List of Guid using Fluent Validation.<br>
  My Ids list should have at least one Guid Id. I did some research and found similar questions answered, and the closest I came to a solution was implementing it like below, but it still doesn't work. When I make a request even if I send the List of Ids with values, it gives me the error message that the Value cannot be null. What am I doing wrong?</p>
  
  <pre><code>    public class Data
      {
          public List&lt;Guid&gt; Ids{ get; set; }
      }
  
      public class DataValidator : AbstractValidator&lt;Data&gt;
      {
          public DataValidator()
          {
              RuleFor(d =&gt; d.Ids).SetCollectionValidator(new GuidValidator());
          }
      }
  
      public class GuidValidator : AbstractValidator&lt;Guid&gt;
      {
          public GuidValidator()
          {
              RuleFor(x =&gt; x).NotNull().NotEmpty();
          }
      }
  </code></pre>
  
  <p>I have tried this validator as well but it didn't work:</p>
  
  <pre><code>    public class DataValidator : AbstractValidator&lt;Data&gt;
      {
          public DataValidator()
          {
              RuleForEach(d =&gt; d.Ids).NotNull().NotEmpty();
          }
      }
  </code></pre>