ExpressVal

Benefits

• Be expressive with your validation rules using Expressions!
• Spend less time thinking about display messages and more time focused on the validation requirement itself!
• Simply implement and test your validation rules!
• Lightweight and nimble!
• Self-contained! (does not rely on any other external framework or project)

Features

• Create rules using lambda expression syntax
• Parses many types of expressions to create canned, English language messages
  • Examples:
  • x => x.Name != null - "Name cannot be null"
  • x => !string.IsNullOrEmpty(x.Name) - "Name cannot be null or blank"
  • x => x.HireDate >= new DateTime(2000,1,1) - "Hire Date must be greater than or equal to January 01, 2000"
  • and many more...
• Canned messages can be overridden with custom message text
• Fluent interface for building up validators
• Multiple options for loading validator rules
  • Discoverable based on assigning the Validator attribute to expressions defined in a field on your entities
  • Implementing IValidatorSource and passing your implementation to the ValidatorEngine