实体验证--根据某个字段判断另一字段是否必填

/// <summary>
    /// 根据传入属性字段决定是否需要必填字段
    /// </summary>
    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field, AllowMultiple = true, Inherited = false)]
    public class CustomRequiredMinValueCompareAttribute : ValidationAttribute
    {
        private MinValueCompareAttribute innerAttribute;
        private string DependentProperty { get; set; }
        private object TargetValue { get; set; }

        public CustomRequiredMinValueCompareAttribute(string dependentProperty, object targetValue, int minimum)
        {
            this.DependentProperty = dependentProperty;
            this.TargetValue = targetValue;
            innerAttribute = new MinValueCompareAttribute(minimum);
        }

        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            var field = validationContext.ObjectInstance.GetType().GetProperty(DependentProperty);
            if (field != null)
            {
                var dependentValue = field.GetValue(validationContext.ObjectInstance, null);
                if (Object.Equals(dependentValue, TargetValue))
                {
                    if (!innerAttribute.IsValid(value))
                        return new ValidationResult(ErrorMessage, new List<string>() { validationContext.MemberName });
                }
            }
            return ValidationResult.Success;
        }
}

以上是匹配最小值

/// <summary>
    /// 根据传入属性字段决定是否需要必填字段
    /// </summary>
    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field, AllowMultiple = true, Inherited = false)]
    public class CustomRequiredValidationAttribute : ValidationAttribute
    {
        private RequiredAttribute innerAttribute = new RequiredAttribute();
        private string DependentProperty { get; set; }
        private object TargetValue { get; set; }

        public CustomRequiredValidationAttribute(string dependentProperty, object targetValue)
        {
            this.DependentProperty = dependentProperty;
            this.TargetValue = targetValue;
        }

        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            var field = validationContext.ObjectInstance.GetType().GetProperty(DependentProperty);
            if (field != null)
            {
                var dependentValue = field.GetValue(validationContext.ObjectInstance, null);
                if (Object.Equals(dependentValue, TargetValue))
                {
                    if (!innerAttribute.IsValid(value))
                        return new ValidationResult(ErrorMessage, new List<string>() { validationContext.MemberName });
                }
            }
            return ValidationResult.Success;
        }
}

匹配必填

使用：

        public bool IsVal { get; set; } = false;

        [CustomRequiredMinValueCompare("IsVal", true, 0, ErrorMessage = "IntValue不能为空！")]
        public int IntValue { get; set; }
        [CustomRequiredValidation("IsVal", true, ErrorMessage = "StringValue不能为空！")]
        public string StringValue { get; set; }