linq contains

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
    public static void Main()
    {
        // 创建一个整数列表
        List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };

        // 检查列表中是否包含数字3
        bool containsThree = numbers.Contains(3);

        Console.WriteLine("列表中包含数字3: " + containsThree); // 输出: 列表中包含数字3: True

        // 使用LINQ查询语法
        bool containsFour = (from num in numbers
                             where num == 4
                             select num).Any();

        Console.WriteLine("列表中包含数字4: " + containsFour); // 输出: 列表中包含数字4: True
    }
}

HashSet<int> numberSet = new HashSet<int>(numbers);
bool containsFive = numberSet.Contains(5); // 更快的查找

bool containsLargeNumber = numbers.AsParallel().Contains(largeNumber);