File: Models\BasketItem.cs
Web Access
Project: src\playground\TestShop\BasketService\BasketService.csproj (BasketService)
using System.ComponentModel.DataAnnotations;
 
namespace BasketService.Models;
 
public class BasketItem : IValidatableObject
{
    public string? Id { get; set; }
    public int ProductId { get; set; }
    public decimal UnitPrice { get; set; }
    public decimal OldUnitPrice { get; set; }
    public int Quantity { get; set; }
 
    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        var results = new List<ValidationResult>();
 
        if (Quantity < 1)
        {
            results.Add(new ValidationResult("Invalid number of units", new[] { "Quantity" }));
        }
 
        return results;
    }
}