LMS.service/LMS.Common/Attributes/NotEmptyAttribute.cs

using System.ComponentModel.DataAnnotations;

namespace LMS.Common.Attributes
{
    [AttributeUsage(AttributeTargets.Property)]
    public class NotEmptyAttribute : ValidationAttribute
    {
        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            if (value is string str && string.IsNullOrWhiteSpace(str))
            {
                return new ValidationResult(ErrorMessage ?? "字段不能为空");
            }
            return ValidationResult.Success;
        }
    }
}