Contains

using System;/* j  a v a  2 s  .c o m*/
using System.Collections;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        bool hasAThree = new int[] { 2, 3, 4 }.Contains(3); // true;

        Console.WriteLine(hasAThree);
    }
}

using System;/*  java2  s.  co m*/
using System.Linq;
using System.Collections;
using System.Collections.Generic;

public class MainClass {
    public static void Main() {
        string[] presidents = {"G", "H", "a", "java2s.com", "over", "Jack"};

        bool contains = presidents.Contains("java2s.com");
        Console.WriteLine(contains);
    }
}

using System;/* java  2  s .  com*/
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MyStringifiedNumberComparer : IEqualityComparer<string> {
    public bool Equals(string x, string y) {
        return (Int32.Parse(x) == Int32.Parse(y));
    }

    public int GetHashCode(string obj) {
        return Int32.Parse(obj).ToString().GetHashCode();
    }
}
public class MainClass {
    public static void Main() {
        string[] stringifiedNums = {"001", "49", "017", "0080", "00027", "2" };
        bool contains = stringifiedNums.Contains("000271",new MyStringifiedNumberComparer());
        Console.WriteLine(contains);
    }
}