DataAnnotations

Package 12: Mapsicle.DataAnnotations

Map and validate against System.ComponentModel.DataAnnotations attributes, with no extra validation library.

using Mapsicle.DataAnnotations;

var result = request.MapAndValidateAnnotations<User>();

if (!result.IsValid)
{
    // { "Email": ["The Email field is required."] }
    IDictionary<string, string[]> errors = result.ErrorsByProperty;
}

// Or validate something you already have
bool ok = user.IsValidAnnotations();
List<ValidationResult> problems = user.GetValidationErrors();

A null source is a failed result, not an exception. Match, OnSuccess and OnFailure are there if you prefer not to branch on IsValid.

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