Release notes

FluentValidation 9 is a major release and includes several breaking changes. Please read the upgrade guide for full details

Changes in 9.0.0

• ASP.NET core auto-validation can now be completely disabled while preserving clientside integration
• Types can now be filtered/skipped when auto-registering with the container
• Service lifetime is now configurable when auto-registering with the container

Changes in 9.0-preview5

• Remove IValidator.Validate(object) overload to improve typesafety (use a context if you need to preserve this behaviour)
• Replace non-generic ValidationContext class with IValidationContext interface
• ChildValidatorAdaptor and IncludeRule now require a generic type parameter indicating the root type being validated
• Expression accessors for comparison properties are now cached where possible
• {ComparisonProperty} placeholder now passes through the same logic as the {PropertyName} placeholder for consistency

Changes in 9.0-preview4

• {CollectionIndex} placeholder can now be accessed in child validators
• Additional ValidationException constructor that allows customising the default message.
• ScalePrecisionValidator algorithm now more consistent with SQL server (#1356)
• Add Icelandic translations of default messages (#1362)
• Additional When predicate overload that takes a ValidationContext
• Fixes to range clientside validators when using datetimes (#1371)
• Drop unsupported .NET Core versions from platform list

Changes in 9.0-preview3

• ASP.NET Core validator provider is now public
• Ensure ASP.NET Core providers aren't registered twice
• SoureLink integration
• Additional overload of SetValidator that receives property value in callback
• PropertyRule.ApplySharedCondition is now public
• Remove lowercase placeholders from ScalePrecisionValidator

Changes in 9.0-preview2

• Transform can now be used to transform a property value to another type prior to validation occurring
• Added WithMessageArgument to test helper extensions
• Added Slovenian translations of default error messages.
• Fixes/better handling of the non-generic overloads of AbstractValidator.Validate
• Removed the deprecated FluentValidation.Internal.Comparer
• TrackingCollection has been marked as internal
• Updated to latest version of Microsoft.NETFramework.ReferenceAssemblies for building net4x targets on non-windows platforms.

Changes in 9.0-preview1

• Removed support for netstandard1.1, netstandard1.6, net45 (Supported platforms are now netstandard2, net461, netcoreapp2.1, netcoreapp3.0, netcoreapp3.1)
• 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.
• Default email validation mode now uses the same logic as ASP.NET Core. Previous regex behaviour is opt-in.
• ComparisonProperty placeholder is now formatted like PropertyName.
• TestHelper syntax improvements
• Equal/NotEqual now perform ordinal comparisons on string properties by default
• Severity can be set with a callback
• PropertyValidator.ShouldValidateAsync reanamed to ShouldValidateAsynchronously to remove confusion where the naming suggested this was an async method
• Removed various methods from MessageFormatter that were deprecated in 8.x
• PropertyValidatorContext.Instance renamed to InstanceToValidate for consistency with ValidationContext.
• Removed DelegatingValidator which was deprecated in 8.x.

Downloads

Binaries can be downloaded from nuget:

• FluentValidation - Main package
• FluentValidation.AspNetCore - ASP.NET Core integration