Better ways to validate using Func

public class Movie
    {
        public string Title { get; set; }

        public int ReleaseYear { get; set; }

        public int Length { get; set; }
    }

    public static class MovieValidator
    {
        public static bool IsValid1(Movie movie)
        {
            if (movie.Title.IsNullOrWhiteSpace()) return false;

            if (movie.ReleaseYear < 1900) return false;

            if (movie.Length <= 0) return false;

            return true;
        }

        public static bool IsValid2(Movie movie)
        {
            Func[] rules =
                                {
                                    m => m.Title.IsNotNullOrWhiteSpace(),
                                    m => m.Length > 0,
                                    m => m.ReleaseYear > 1900
                                };

            return rules.All(rule => rule(movie));
        }

        public static bool IsNullOrWhiteSpace(this string value)
        {
            return string.IsNullOrEmpty(value) || value.Length.Equals(0);
        }

        public static bool IsNotNullOrWhiteSpace(this string value)
        {
            return !value.IsNullOrWhiteSpace();
        }
    }

Named Parameters, Extension methods and Fluent API's

Let's see how above three techniques help us to write a better code

    public interface ITask
    {
    }

    public class CopyFile : ITask
    {
    }

    public class ScheduledTask
    {
        public ScheduledTask(ITask task, TimeSpan runEvery, TimeSpan expiresOn)
        {
            this.Task = task;
            this.RunEvery = runEvery;
            this.ExpiresOn = expiresOn;
        }

        public ITask Task { get; set; }

        public TimeSpan RunEvery { get; set; }

        public TimeSpan ExpiresOn { get; set; }
    }

    public static class Worker
    {
        public void DoWork()
        {
            //var task = new ScheduledTask(new CopyFile(),
            //                    runEvery : new TimeSpan(0,0,5),
            //                    expiresOn : new TimeSpan(0,0,5));

             var task = new ScheduledTask(new CopyFile(),
                                runEvery : 2.Minutes(),
                                expiresOn : 3.Days());

             var completed = 2.Minutes().Ago();
        }

        public static TimeSpan Minutes(this int value)
        {
            return new TimeSpan(0, 0, value, 0);
        }

        public static TimeSpan Days(this int value)
        {
            return new TimeSpan(value, 0, 0, 0, 0);
        }

        public static DateTime Ago(this TimeSpan value)
        {
            return DateTime.Now - value;
        }
    }