csharp dto_Address的自定义验证器

Posted 2021-05-12

using System.ComponentModel.DataAnnotations;

namespace Springsteen.WebApi.Contract
{
    public class RequiredUnlessSeqNumAttribute : ValidationAttribute
    {

        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            int seqNum;
            if (int.TryParse(validationContext.ObjectType.GetProperty("seqNum").GetValue(validationContext.ObjectInstance, null).ToString(), out seqNum))
            {
                if (seqNum == 0)
                {
                    // enforce required-ness
                    if (value == null)
                    {
                        return new ValidationResult(FormatErrorMessage(validationContext.DisplayName));
                    }
                }  
            }

            return null;
        }

    }
}