asp.net mvc重写RequestValidator

  /// <summary>
    /// <httpRuntime requestValidationType="xxx.CustomRequestValidator" />
    /// </summary>
    public class CustomRequestValidator : RequestValidator
    {
        public readonly static object CustomRequestValidatorKey = new object();

        protected override bool IsValidRequestString(HttpContext context, string value, RequestValidationSource requestValidationSource,
            string collectionKey, out int validationFailureIndex)
        {
            var obj = context.Items[CustomRequestValidatorKey];
            if (obj != null)
            {
                var notValid = (RequestNotValidationSource)obj;
                if (notValid == RequestNotValidationSource.All)
                {
                    validationFailureIndex = 0;
                    return true;
                }
                RequestNotValidationSource tmp;
                if (Enum.TryParse(requestValidationSource.ToString(), out tmp) && notValid.HasFlag(tmp))
                {
                    validationFailureIndex = 0;
                    return true;
                }
            }
            return base.IsValidRequestString(context, value, requestValidationSource, collectionKey, out validationFailureIndex);
        }
    }

    /// <summary>
    /// 重写验证逻辑
    /// </summary>
    [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, Inherited = true, AllowMultiple = false)]
    public class CustomRequestValidatorAttribute : FilterAttribute, IAuthorizationFilter
    {
        /// <summary>
        /// 不验证哪些数据
        /// </summary>
        public RequestNotValidationSource? NotValidationSource { get; set; }

        public CustomRequestValidatorAttribute()
        {
            NotValidationSource = null;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="notValidationSource">不验证哪些数据</param>
        public CustomRequestValidatorAttribute(RequestNotValidationSource notValidationSource)
        {
            NotValidationSource = notValidationSource;
        }

        public virtual void OnAuthorization(AuthorizationContext filterContext)
        {
            filterContext.HttpContext.Items[CustomRequestValidator.CustomRequestValidatorKey] = NotValidationSource;
        }

    }

    /// <summary>
    /// 不验证哪些数据
    /// </summary>
    [Flags]
    public enum RequestNotValidationSource
    {
        QueryString = 1,
        Form = 2,
        Cookies = 4,
        Files = 8,
        RawUrl = 16,
        Path = 32,
        PathInfo = 64,
        Headers = 128,
        All = 256
    }