LINQ -分组方式- IEnumerable返回

var students = new List<Student>
{
    new Student { Name = "Alice", Age = 20, Grade = "A" },
    new Student { Name = "Bob", Age = 21, Grade = "B" },
    new Student { Name = "Charlie", Age = 20, Grade = "A" },
    new Student { Name = "David", Age = 22, Grade = "C" },
    new Student { Name = "Eve", Age = 21, Grade = "B" }
};

var groupedStudents = from student in students
                      group student by student.Grade into g
                      select new { Grade = g.Key, Students = g };

foreach (var group in groupedStudents)
{
    Console.WriteLine($"Grade: {group.Grade}");
    foreach (var student in group.Students)
    {
        Console.WriteLine($"Name: {student.Name}, Age: {student.Age}");
    }
    Console.WriteLine();
}