FluentValidation 8.5.0-preview4

A validation library for .NET that uses a fluent interface to construct strongly-typed validation rules.

Showing the top 20 packages that depend on FluentValidation.

Packages Downloads
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
19
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
20
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
21
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
22
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
24
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
21

FluentValidation 8 is a major release. Please read the upgrade notes at https://fluentvalidation.net/upgrading-to-8

Changes in 8.5.0:

  • Add additional overload of the EmailAddress validator for compatibility with ASP.NET Core's default email validation.
  • Simplify the advanced testhelper syntax.
  • Add support for ASP.NET Core 3.
  • Add support for defining child rules inline.
  • ValidatorDescriptor now has consistent handling of model-level rules.
  • RuleForEach can now access collection index in error message with placeholder.
  • Welsh language translations of default error messages.
  • Hungrian language translations of default error messages.
  • Indonesian language translations of default error messages.
  • Using RuleForEach combined with When is now more intuitive.

Changes in 8.4.0:

  • Added simplified version of several messages across all translations to aid with ASP.NET Clientside validation.
  • New enum validator for string properties.

Changes in 8.3.0:

  • Fix issue in ASP.NET Core integration with GetServiceProvider not working correctly when invoked against a CustomContext/MessageBuilderContext.
  • Improved how LanguageStringSource works with error-code overrides.
  • Fix thread-safety issue with use of PropertyValidatorOptions.Empty (now removed).
  • Improved how calls to When/Unless are handled internally.
  • DelegatingValidator is now marked as deprecated.
  • Improvements to Croatian language translations.
  • Improvements to Georgian language translations.
  • Resolved subtle bug where top-level WhenAsync wouldn't work correctly when wrapping a top-level call to When.

Changes in 8.2.3:

  • Fix issue in WebApi integration where DataAnnotations validators could generate duplicate messages when in the same project as FluentValidation.

Changes in 8.2.2:

  • Fix FluentValidation.DependencyInjection package name.

Changes in 8.2.1:

  • Resolved issue using InjectValidator with RuleForEach.
  • Add support for a default IValidatorInterceptor to be registered with the ASP.NET Core Service Provider.

Changes in 8.2.0:

  • Add extensions for injecting child validators using the ASP.NET Core Service Provider.
  • Implement RuleFor(...).ForEach(...) as an alternative to RuleForEach.
  • WithLocalizedMessage is deprecated. Use the overload of WithMessage that takes a Func instead.

Changes in 8.1.3:

  • Resolved issue where clientside validation was incorrectly generating metadata for rules with shared conditions.
  • ScalePrecisionValidator now has a public method in the fluent interface.
  • Fix placeholder names in ScalePrecisionValidator for consistency.
  • Updates to Portuguese (Brazil) translations.

Changes in 8.1.2:

  • Fix issue where shared When/Unless conditions didn't execute correctly when used with RuleForEach.

Changes in 8.1.1:

  • Added RuleSetsExecuted property on ValidationResult.
  • Resolved issue introduced in 8.1 where the shared condition cache does not work correctly with RuleForEach (#970).

Changes in 8.1:

  • Add format support in message placeholders.
  • Added support for overriding indexers for collection rules.
  • Allow error codes to be used to override localization key in the Language Manager.
  • Additional error details are now shown in the ShouldNotHaveValidationErrorFor test extension.
  • Conditions defined with root-level When/WhenAsync/Unless/UnlessAsync are now only executed once (instead of once for each rule).
  • Support Otherwise method chained from root-level When/WhenAsync/Unless/UnlessAsync.
  • Minor wording changes to default English error messages.
  • Japanese translation of the default error messages.
  • Added Skip property to MVC5's CustomizeValidatorAttribute for parity with AspNetCore and WebApi.
  • Remove type constraint on the OverridePropertyName overload that takes an expression.

Added Skip property to MVC5's CustomizeValidatorAttribute to bring parity with AspNetCore and WebApi integration. Changes in 8.0:

  • Support validating only specific properties by path.
  • Added OnFailure method
  • Deprecated RuleFor(..).SetCollectionValidator in favour of RuleForEach(...).SetValidator
  • IStringSource.GetString now takes a validation context instead of a model instance.
  • Introduce PropertyValidatorOptions in order to clean up the IPropretyValidator interface.
  • Moved the legacy ValidatorAttribute and AttributedValidatorFactory into a separate FluentValidation.Attributes package.
  • Remove the pre-7.0 localization mechanism
  • Remove the pre-7.0 methods for custom validation
  • Removed many other deprecated methods

Full release notes can be found at https://github.com/JeremySkinner/FluentValidation/blob/master/Changelog.txt

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12.1.1 9 18.12.2025
12.1.0 12 09.11.2025
12.0.0 17 23.05.2025
12.0.0-preview1 19 12.01.2025
11.12.0 12 09.11.2025
11.11.0 26 02.12.2024
11.10.0 20 01.10.2024
11.9.2 20 12.01.2025
11.9.1 18 15.01.2025
11.9.0 22 10.01.2025
11.8.1 22 05.01.2025
11.8.0 17 15.01.2025
11.7.1 19 15.01.2025
11.7.0 20 08.01.2025
11.6.0 17 15.01.2025
11.5.2 19 08.01.2025
11.5.1 17 23.01.2025
11.5.0 20 05.01.2025
11.4.0 19 15.01.2025
11.3.0 17 09.01.2025
11.2.2 22 07.01.2025
11.2.1 18 15.01.2025
11.2.0 20 14.01.2025
11.1.1 17 07.01.2025
11.1.0 18 23.01.2025
11.0.3 16 12.01.2025
11.0.2 18 28.01.2025
11.0.1 16 12.01.2025
11.0.0 20 10.01.2025
10.4.0 17 15.01.2025
10.3.6 16 15.01.2025
10.3.5 17 15.01.2025
10.3.4 17 10.01.2025
10.3.3 18 15.01.2025
10.3.1 23 10.01.2025
10.3.0 18 12.01.2025
10.2.3 22 15.01.2025
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10.2.1 18 15.01.2025
10.2.0 17 15.01.2025
10.1.0 17 15.01.2025
10.0.4 19 15.01.2025
9.5.4 20 15.01.2025
9.5.3 20 15.01.2025
9.5.2 20 14.01.2025
9.5.1 27 10.01.2025
9.5.0 24 15.01.2025
9.4.0 23 10.01.2025
9.3.0 18 10.01.2025
9.3.0-preview3 18 10.01.2025
9.3.0-preview2 18 09.01.2025
9.3.0-preview1 20 19.02.2025
9.2.2 19 10.01.2025
9.2.1 19 09.01.2025
9.2.0 26 15.01.2025
9.1.3 19 15.01.2025
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9.1.1 22 10.01.2025
9.1.0 22 10.01.2025
9.0.1 21 14.01.2025
9.0.0-preview5 18 06.01.2025
9.0.0-preview4 19 07.01.2025
9.0.0-preview3 20 06.01.2025
9.0.0-preview2 21 07.01.2025
9.0.0-preview1 18 12.01.2025
8.6.3 21 15.01.2025
8.6.2 18 15.01.2025
8.6.1 21 15.01.2025
8.6.0 20 15.01.2025
8.5.1 20 15.01.2025
8.5.0 20 15.01.2025
8.5.0-preview5 21 10.01.2025
8.5.0-preview4 19 11.01.2025
8.5.0-preview3 17 10.01.2025
8.5.0-preview2 18 06.01.2025
8.5.0-preview1 18 10.01.2025
8.4.0 19 28.01.2025
8.3.0 18 10.01.2025
8.2.3 30 15.01.2025
8.2.2 19 05.01.2025
8.2.1 19 28.01.2025
8.2.0 20 15.01.2025
8.1.3 19 15.01.2025
8.1.2 18 12.01.2025
8.1.1 19 10.01.2025
8.1.0 18 14.01.2025
8.1.0-preview2 19 13.01.2025
8.1.0-preview1 18 23.01.2025
8.0.101 18 10.01.2025
8.0.100 23 15.01.2025
8.0.0 20 15.01.2025
8.0.0-rc1 18 10.01.2025
8.0.0-preview4 17 05.01.2025
8.0.0-preview3 22 07.01.2025
8.0.0-preview2 20 07.01.2025
7.6.105 18 15.01.2025
7.6.104 17 15.01.2025
7.6.103 19 15.01.2025
7.6.102 21 11.01.2025
7.6.101 22 15.01.2025
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7.6.0 22 12.01.2025
7.6.0-preview1 17 07.01.2025
7.5.2 19 10.01.2025
7.5.1 20 15.01.2025
7.5.0 20 15.01.2025
7.4.0 20 15.01.2025
7.3.4 24 10.01.2025
7.3.3 20 15.01.2025
7.3.2 20 15.01.2025
7.3.1 19 15.01.2025
7.3.0 19 15.01.2025
7.3.0-beta3 17 28.01.2025
7.3.0-beta2 18 28.01.2025
7.3.0-beta1 17 28.01.2025
7.2.1 21 09.01.2025
7.2.0 19 15.01.2025
7.2.0-beta3 20 28.01.2025
7.2.0-beta2 16 27.01.2025
7.2.0-beta1 19 28.01.2025
7.1.1 22 10.01.2025
7.1.0 24 15.01.2025
7.1.0-beta1 21 10.01.2025
7.0.3 19 15.01.2025
7.0.2 18 28.01.2025
7.0.1 22 10.01.2025
7.0.0 19 15.01.2025
7.0.0-beta3 24 13.01.2025
7.0.0-beta2 24 10.01.2025
7.0.0-beta1 19 15.01.2025
6.4.1 20 28.01.2025
6.4.1-beta1 16 28.01.2025
6.4.0 25 10.01.2025
6.4.0-rc4 19 10.01.2025
6.4.0-rc3 26 10.01.2025
6.4.0-rc2 19 10.01.2025
6.4.0-rc1 17 10.01.2025
6.4.0-beta9 18 10.01.2025
6.4.0-beta8 16 28.01.2025
6.4.0-beta7 17 07.01.2025
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6.4.0-beta5 18 28.01.2025
6.4.0-beta4 18 13.01.2025
6.4.0-beta3 17 28.01.2025
6.4.0-beta2 16 27.01.2025
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6.3.4-alpha 19 10.01.2025
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6.1.0 22 07.01.2025
6.0.2 22 11.01.2025
6.0.1 18 24.01.2025
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