RzR.Validation.Attributes 3.0.0.6710

RzR.Validation.Attributes is a .NET library that extends System.ComponentModel.DataAnnotations with ~58 ready-to-use ValidationAttribute subclasses covering presence checks, comparisons, string rules, date/time constraints, format patterns, identity validation, collection guards, conditional requirements, and object-level cross-property rules. Every attribute plugs directly into the standard Validator API - no extra infrastructure needed.

Install-Package RzR.Validation.Attributes

Features at a glance

Full attribute reference, constructor signatures, and edge-case notes are in docs/usage.md.

Quick start

using RzR.Validation.Attributes.Attributes.Require;
using RzR.Validation.Attributes.Attributes.String;
using RzR.Validation.Attributes.Attributes.Greater;
using System.ComponentModel.DataAnnotations;
using System.Collections.Generic;

public class CreateOrderRequest
{
    [ValRequiredNotNull]
    [ValRequiredNotEmpty]
    public string CustomerName { get; set; }

    [ValGreaterThan(0)]
    public decimal Amount { get; set; }

    [ValMinLength(2)]
    [ValMaxLength(100)]
    public string Notes { get; set; }
}

// Validate using the standard DataAnnotations API:
var model = new CreateOrderRequest { CustomerName = "Acme", Amount = 49.99m };
var results = new List<ValidationResult>();
bool isValid = Validator.TryValidateObject(model, new ValidationContext(model), results, validateAllProperties: true);

Good to know

• Custom error messages. Every attribute accepts an optional trailing string userMessage constructor parameter that overrides the default message.
• Null is invalid by design. All non-presence attributes (comparisons, string rules, format, numeric, etc.) reject null. Each rule is self-contained. When a field is truly optional, pair the non-presence attribute with a presence attribute only if the field is present - or handle nullability in your model before validation.
• Object-level attributes require validateAllProperties: true. The class-targeted attributes (ValAtLeastOneOf, ValMutuallyExclusive, ValExactlyOneOf, ValChronological) and the cross-property conditional attributes (ValRequiredIf, ValRequiredUnless, ValCompareProperty) only execute when you call Validator.TryValidateObject(..., validateAllProperties: true).
• ValAjaxOnly is not a security control. It validates a caller-supplied bool flag only. Real AJAX enforcement must be done server-side via an action filter or middleware that reads the X-Requested-With header.