using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {       

        foreach( var item in SomeTypeRepository.Method(new Specification("salman", 1, 2)))

        {

            Console.WriteLine(item.Property2);

        }

    }

}

​

public interface ISpecification<T>

{

    Func<T, bool> Predicate { get; }

}

​

public class Specification : ISpecification<SomeType>

{

    private string _filter1;

    private int _filter2;

    private int _filter3;   

    public Specification(string filter1, int filter2, int filter3)

    {

        _filter1 = filter1;

        _filter2 = filter2;

        _filter3 = filter3;

    }

    public Func<SomeType, bool> Predicate

    {

        get

        {

            Func<string, bool> contains = x => x.ToLower().Contains(_filter1);

            Func<int, bool> between = x => _filter2 <= x && x <= _filter3;

            Func<SomeType, bool> predicate = x => contains(x.Property2) && between(x.Property1);

            return predicate;

        }

    }

}

​

public class SomeTypeRepository

{

    private static readonly SomeType[] _items;

    static SomeTypeRepository()

    {

        _items = new SomeType[]

        {

            new SomeType { Property1 = 1, Property2 = "Husain" },

            new SomeType { Property1 = 2, Property2 = "Salman" }

        };

    }

    public static IEnumerable<SomeType> Method(ISpecification<SomeType> specification)

    {

        return _items.Where(specification.Predicate);

    }

}

​

public class SomeType

{

    public int Property1 { get; set; }

    public string Property2 { get; set; }

}