Release notes

Please read the upgrade guide if you are moving from 8.x to 9.x

Changes in 9.5.0

• Introduce new syntax for applying transformations and deprecate the old syntax (#1613)

Changes in 9.4.0

• ChildRules now work as expected when inside a ruleset (#1597)
• Added ImplicitlyValidateRootCollectionElements option to MVC integration (#1585)

Changes in 9.3.0

• Support for .NET 5 and ASP.NET Core 5
• 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) (#1541)
• RuleSetForClientSideMessagesAttribute now works in Razor pages (netcore 3.1 and net 5.0 only) (#1544)
• Fixes to Spanish translations.

Changes in 9.2.2

• Fix one of the inheritance validator overloads not working correctly (#1528)

Changes 9.2.1

• Add non-generic extensibility point to inheritance validator
• Updates to Persian translations (#1513)
• Added Bengali translations (#1517)

Changes in 9.2.0

• Add inheritance validator (#1237) - see https://docs.fluentvalidation.net/en/latest/inheritance.html
• Various performance improvements

Changes in 9.1.3

• Fix an issue with IncludeRulesNotInRuleSet not working correctly (#1493)

Changes in 9.1.2

• Make the ValidationContext.ThrowOnFailures getter public.

Changes in 9.1.1

• Update incorrect wording in CascadeMode.StopOnFirstFailure deprecation warning.

Changes in 9.1.0

• Add new Validate extension methods that allow options to be configured using a strategy (#1467)
• 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 (#1162)
• Make ruleset separator character splitting consistent (#1424)
• Transform now works with RuleForEach (#1450)
• Introduce constants for rulesets (#1435)
• Resolve issue when attempting to use asynchronous conditions in a synchornous validaiton run (#1438)
• Added asynchronous versions of the TestHelper methods (#1423)

Example of using the new validation strategy:

// Validate specific rulesets
validator.Validate(instance, opt => {
  opt.IncludeRuleSets("MyRuleSet", "SomeOtherRuleSet");
  
  // Can also force rules not in a ruleset to be run
  opt.IncludeRulesNotInRuleSet();
});

// Validate specific properties
validator.Validate(instance, opt => {
  opt.IncludeProperties("Forename", "Surname");
  // or
  opt.IncludeProperties(x => x.Surname, x.Forename);
});

// Throw exceptions on failure
validator.Validate(instance, opt => {
   opt.ThrowOnFailures();
});

// Combine various options
validator.Validate(instance, opt => {
  opt.IncludeRuleSets("MyRuleSet", "SomeOtherRuleSet").IncludeRulesNotInRuleSet();
  opt.ThrowOnFailures();
});

Downloads

Binaries can be downloaded from nuget:

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