using System.Collections.Generic;

using System.Linq;

using System;

public class Program

{

    public static void Main()

    {

        var three = new SomeClass {SomeProperty = 3};

        var someList = new List<SomeClass>{ three };

        var where = someList.Where(item => item.SomeProperty == 3).Any();

        var contains = someList.Exists(item => item.SomeProperty == 3);

        Console.WriteLine(where);

        Console.WriteLine(contains);

    }

}

​

public class SomeClass

{

    public int SomeProperty {get; set;}

}