FluentValidation 9.3.0-preview3

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
16
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
17
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
18
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
18

FluentValidation 9 is a major release. Please read the upgrade notes at https://docs.fluentvalidation.net/en/latest/upgrading-to-9.html

Changes in 9.3.0:

  • Improvements to LanguageManager's lazy loading of resources.
  • Deprecate IStringSource and its implementors. Use delegates instead.
  • CustomizeValidatorAttribute now works in Razor pages (netcore 3.1 and net 5.0 only)
  • RuleSetForClientSideMessagesAttribute now works in Razor pages (netcore 3.1 and net 5.0 only)

Changes in 9.2.2:

  • Fix one of the inheritance validator overloads not working correctly.

Changes in 9.2.1:

  • Add non-generic Add method to inheritance validator.
  • Updates to Persian translations.
  • Added Bengali translations.

Changes in 9.2.0:

  • Add inheritance validator
  • Performance improvements

Changes in 9.1.3:

  • Fix an issue with IncludeRulesNotInRuleSet not working correctly

Changes in 9.1.2:

  • Make the ValidationContext.ThrowOnFailures getter public.

Changes in 9.1.1:

  • Fix an incorrect deprecation message.

Changes in 9.1:

  • Make ruleset separator character splitting consistent
  • Transform now works with RuleForEach
  • Introduce constants for rulesets
  • Resolve issue when attempting to use asynchronous conditions in a synchornous validaiton run
  • Added asynchronous versions of the TestHelper methods.
  • Introduce CascadeMode.Stop and deprecate CascadeMode.StopOnFirstFailure to resolve confusion/abiguity about setting the cascade mode at validator-level (#1437)
  • RaiseValidationException can be overridden to customize the exception throwing process
  • Add new Validate extension methods that allow options to be configured using a strategy

Changes in 9.0.0:

  • Removed support for netstandard1.1 and netstandard1.6
  • Removed support for end-of-life .NET Core versions (2.2 and 3.0). LTS versions are supported (2.1 and 3.1)
  • Default email validation mode now uses the same logic as ASP.NET Core. Previous regex behaviour is opt-in.
  • TestHelper advanced mode now has more features (see https://docs.fluentvalidation.net/en/latest/testing.html#advanced-test-extensions)
  • Equal/NotEqual now perform ordinal comparison when used with string properties
  • Severity can now be set dynamically with a callback
  • Removed WithLocalizedMessage (WithMessage that takes a callback is the replacement)
  • Removed ResourceName from ValidationFailure
  • Removed ResourceName and ResourceType from IStringSource.
  • Removed SetCollectionValidator which was deprecated in 8.0
  • Additional overload of OnAnyFailure that can receive a collection of validation failures
  • Remove DisplayAttribute integration and reference to DataAnnotations.
  • ComparisonProperty placeholder is now formatted like PropertyName
  • Translations of default error messages into other languages are now lazily-loaded
  • Added Slovenian translations of default error messages.
  • Added Icelandic translations of default error messages.
  • Added WithMessageArgument to the test helpers.
  • Add additional overload of SetValidator that takes a Func that receives the current property value.
  • ASP.NET Core: FluentValidationModelValidatorProvider and FluentValidationModelValidator are now public.
  • Work around a bug in ASP.NET Core's integration testing components that can cause ConfigureServices to run multiple times.
  • SourceLink integration.
  • placeholder can now be accessed in child validators.
  • Additional ValidationException constructor that allows using both the default message and a custom one together.
  • ScalePrecisionValidator algorithm now matches SQL Server.
  • Additional overload of the When methods that contain the validation context.
  • Automatically scanned types can be excluded when calling RegisterValidatorsFromAssemblyContaining in ASP.NET Core projects.
  • New AutomaticValidationEnabled property for use in ASP.NET Core projects (defaults to true).

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

.NET Framework 4.6.1

  • No dependencies.

.NET 5.0

  • No dependencies.

.NET Standard 2.0

  • No dependencies.

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12.1.1 4 18.12.2025
12.1.0 9 09.11.2025
12.0.0 13 23.05.2025
12.0.0-preview1 15 12.01.2025
11.12.0 7 09.11.2025
11.11.0 18 02.12.2024
11.10.0 17 01.10.2024
11.9.2 17 12.01.2025
11.9.1 15 15.01.2025
11.9.0 19 10.01.2025
11.8.1 19 05.01.2025
11.8.0 14 15.01.2025
11.7.1 16 15.01.2025
11.7.0 17 08.01.2025
11.6.0 14 15.01.2025
11.5.2 16 08.01.2025
11.5.1 14 23.01.2025
11.5.0 17 05.01.2025
11.4.0 16 15.01.2025
11.3.0 14 09.01.2025
11.2.2 18 07.01.2025
11.2.1 15 15.01.2025
11.2.0 17 14.01.2025
11.1.1 13 07.01.2025
11.1.0 14 23.01.2025
11.0.3 13 12.01.2025
11.0.2 15 28.01.2025
11.0.1 13 12.01.2025
11.0.0 16 10.01.2025
10.4.0 14 15.01.2025
10.3.6 13 15.01.2025
10.3.5 14 15.01.2025
10.3.4 13 10.01.2025
10.3.3 14 15.01.2025
10.3.1 20 10.01.2025
10.3.0 15 12.01.2025
10.2.3 19 15.01.2025
10.2.2 15 15.01.2025
10.2.1 15 15.01.2025
10.2.0 14 15.01.2025
10.1.0 14 15.01.2025
10.0.4 16 15.01.2025
9.5.4 15 15.01.2025
9.5.3 15 15.01.2025
9.5.2 15 14.01.2025
9.5.1 22 10.01.2025
9.5.0 19 15.01.2025
9.4.0 18 10.01.2025
9.3.0 13 10.01.2025
9.3.0-preview3 13 10.01.2025
9.3.0-preview2 14 09.01.2025
9.3.0-preview1 16 19.02.2025
9.2.2 14 10.01.2025
9.2.1 14 09.01.2025
9.2.0 21 15.01.2025
9.1.3 14 15.01.2025
9.1.2 15 15.01.2025
9.1.1 17 10.01.2025
9.1.0 18 10.01.2025
9.0.1 17 14.01.2025
9.0.0-preview5 14 06.01.2025
9.0.0-preview4 16 07.01.2025
9.0.0-preview3 16 06.01.2025
9.0.0-preview2 18 07.01.2025
9.0.0-preview1 15 12.01.2025
8.6.3 17 15.01.2025
8.6.2 15 15.01.2025
8.6.1 16 15.01.2025
8.6.0 15 15.01.2025
8.5.1 15 15.01.2025
8.5.0 15 15.01.2025
8.5.0-preview5 18 10.01.2025
8.5.0-preview4 13 11.01.2025
8.5.0-preview3 14 10.01.2025
8.5.0-preview2 13 06.01.2025
8.5.0-preview1 15 10.01.2025
8.4.0 14 28.01.2025
8.3.0 14 10.01.2025
8.2.3 24 15.01.2025
8.2.2 14 05.01.2025
8.2.1 14 28.01.2025
8.2.0 15 15.01.2025
8.1.3 14 15.01.2025
8.1.2 13 12.01.2025
8.1.1 14 10.01.2025
8.1.0 14 14.01.2025
8.1.0-preview2 15 13.01.2025
8.1.0-preview1 14 23.01.2025
8.0.101 14 10.01.2025
8.0.100 19 15.01.2025
8.0.0 15 15.01.2025
8.0.0-rc1 14 10.01.2025
8.0.0-preview4 14 05.01.2025
8.0.0-preview3 17 07.01.2025
8.0.0-preview2 16 07.01.2025
7.6.105 15 15.01.2025
7.6.104 14 15.01.2025
7.6.103 15 15.01.2025
7.6.102 17 11.01.2025
7.6.101 18 15.01.2025
7.6.100 16 15.01.2025
7.6.0 17 12.01.2025
7.6.0-preview1 13 07.01.2025
7.5.2 14 10.01.2025
7.5.1 15 15.01.2025
7.5.0 14 15.01.2025
7.4.0 15 15.01.2025
7.3.4 18 10.01.2025
7.3.3 15 15.01.2025
7.3.2 15 15.01.2025
7.3.1 14 15.01.2025
7.3.0 15 15.01.2025
7.3.0-beta3 13 28.01.2025
7.3.0-beta2 14 28.01.2025
7.3.0-beta1 14 28.01.2025
7.2.1 16 09.01.2025
7.2.0 14 15.01.2025
7.2.0-beta3 16 28.01.2025
7.2.0-beta2 13 27.01.2025
7.2.0-beta1 14 28.01.2025
7.1.1 17 10.01.2025
7.1.0 19 15.01.2025
7.1.0-beta1 17 10.01.2025
7.0.3 15 15.01.2025
7.0.2 14 28.01.2025
7.0.1 18 10.01.2025
7.0.0 15 15.01.2025
7.0.0-beta3 21 13.01.2025
7.0.0-beta2 21 10.01.2025
7.0.0-beta1 15 15.01.2025
6.4.1 16 28.01.2025
6.4.1-beta1 13 28.01.2025
6.4.0 21 10.01.2025
6.4.0-rc4 16 10.01.2025
6.4.0-rc3 21 10.01.2025
6.4.0-rc2 16 10.01.2025
6.4.0-rc1 14 10.01.2025
6.4.0-beta9 15 10.01.2025
6.4.0-beta8 13 28.01.2025
6.4.0-beta7 14 07.01.2025
6.4.0-beta6 20 07.01.2025
6.4.0-beta5 14 28.01.2025
6.4.0-beta4 15 13.01.2025
6.4.0-beta3 14 28.01.2025
6.4.0-beta2 13 27.01.2025
6.4.0-beta10 13 07.01.2025
6.4.0-beta1 14 29.01.2025
6.3.4-alpha 14 10.01.2025
6.3.3-alpha 14 10.01.2025
6.2.1 15 28.01.2025
6.2.1-beta1 13 27.01.2025
6.2.0 14 28.01.2025
6.2.0-beta1 13 07.01.2025
6.1.0 18 07.01.2025
6.0.2 19 11.01.2025
6.0.1 14 24.01.2025
6.0.0 14 28.01.2025
5.6.2 16 10.01.2025
5.6.1 15 15.01.2025
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5.3.0 15 15.01.2025
5.2.0 15 15.01.2025
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5.0.0.1 17 15.01.2025
4.0.0.1 15 10.01.2025
4.0.0 13 23.01.2025
3.4.6 15 14.01.2025
3.4.0 15 15.01.2025
3.3.1 16 15.01.2025
3.2.0 12 15.01.2025
3.1.0 18 10.01.2025
3.0.0.1 16 15.01.2025
3.0.0 15 15.01.2025
2.0.0 15 28.01.2025
1.3.0 17 10.01.2025