从foreach中的GroupBy键获取特定值

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

class Program
{
    static void Main()
    {
        // 创建一个包含学生信息的集合
        List<Student> students = new List<Student>()
        {
            new Student { Name = "张三", Grade = "一年级" },
            new Student { Name = "李四", Grade = "二年级" },
            new Student { Name = "王五", Grade = "一年级" },
            new Student { Name = "赵六", Grade = "三年级" },
            new Student { Name = "钱七", Grade = "二年级" }
        };

        // 使用GroupBy方法对学生集合按年级进行分组
        var groups = students.GroupBy(s => s.Grade);

        // 遍历每个分组，并获取特定的值
        foreach (var group in groups)
        {
            Console.WriteLine("年级：" + group.Key);

            // 获取每个分组中的学生姓名
            foreach (var student in group)
            {
                Console.WriteLine("姓名：" + student.Name);
            }
        }
    }
}

class Student
{
    public string Name { get; set; }
    public string Grade { get; set; }
}