CreateException.cs

private static Exception Create<T>(string message, T exception)
            where T : Exception
        {
            Type exceptionType = typeof(T);

            if (typeof(Exception).IsAssignableFrom(exceptionType))
                return new Exception(message, exception);

            MethodInfo method = _createDel.Method.GetGenericMethodDefinition().MakeGenericMethod(exceptionType);
            return method.Invoke(null, new object[] { message, exception }) as Exception;
        }

        private static Exception Create<T>(string message, Exception innerException)
            where T : Exception
        {
            Type type = typeof(T);
            Type[] argTypes = new[] { typeof(string), typeof(Exception) };
            ConstructorInfo ctor = type.GetConstructor(argTypes);

            if (ctor == null)
                return null;

            try
            {
                return (T)ctor.Invoke(new object[] { message, innerException });
            }
            catch
            {
                return null;
            }
        }

        private static Delegate _createDel = (Func<string, Exception, Exception>)ExceptionFilter.Create<Exception>;