public bool BeValid(ValidationErrors <YourSharedModel> validationFailures, YourSharedModel sharedModel, ValidationContext <YourSharedModel> validationContext)
 {
     for (var m in sharedModel.Models)
     {
         var result = YourValidationMethod(m);
         if (!result.Success)
         {
             validationFailures.AddFailureFor(x => m, result.ErrorMessage);
             return(false);
         }
     }
     return(true);
 }