Validating primitive types

I’m trying to find a way how I can use built-in validators to validate primitive types like strings or ints. For example, I would like to be able to use EmailValidator to validate a string value (not a string property of a complex type) by calling something like Validate. But EmailValidator is IPropertyValidator, not IValidator.

Any ideas how to use FluentValidation to validate primitive types?

[JeremySkinner]

Sure, here’s an example that chains multiple rules on a string property, within an extension method.

// In the validator
RuleFor(x => x.Surname).CustomSurnameValidation();

// Custom extensions class
public static class MyExtensions {

  // Generic type is hard-coded to string, menaing this method will only appear for string properties.
  // If you wanted it to appear for *all* properties, introduce a second type-parameter called TProperty
  public static IRuleBuilderOptions<T, string> CustomSurnameValidation<T>(this IRuleBuilder<T, string> rule) {
    return rule.NotNull().NotEqual("foo");
  } 
}

This is actually how all of FV’s default validation rules (NotNull, NotEmpty etc) work- they’re all extesnions on IRuleBuilder that perform certain actions (usually calling SetValidator to encapsulate within a custom property validator)

[JeremySkinner]

Yes, you have a couple of options. You can use the approach I documented above, by creating an AbstractValidator instance that acts on strings. The other option is to write an extension that wraps the multiple calls to RuleFor.