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c#fluentvalidation

Combine multiple FluentValidation conditions with or?

I have a property where I want to check if it is either empty or in a specific format. I know I could put both conditions in one regex, but using something like Empty().Or.Matches(...) would be far easier to read - is something like that possible using FluentValdations?

So current code:

RuleFor(x => x.Property)
    .Matches(@"^$|^[0-9]+$"); // did not check the regex, but for this example it should not matter

I would prefer something like that for better readability:

RuleFor(x => x.Property)
    .Empty().Or().Matches(@"^[0-9]+$");
Solution

  • With the method's that are available now, it would have to by chaining or's || in the Must method.

    Regex regex = new Regex("\\b(jack|jill)\\b");
RuleFor(validateField => validateField.Name)
  .Must(name => string.IsNullOrEmpty(name) || regex.IsMatch(name))
  .WithMessage("Name must be empty or 'jack' or 'jill'");

    DotNet fiddle