LINQ - GroupBy键,然后将每个分组项放入单独的"桶"中

var students = new List<Student>
{
    new Student { Name = "Alice", Grade = 1 },
    new Student { Name = "Bob", Grade = 2 },
    new Student { Name = "Charlie", Grade = 1 },
    new Student { Name = "David", Grade = 3 },
    new Student { Name = "Eve", Grade = 2 },
};

var groupedStudents = from student in students
                      group student by student.Grade into studentGroup
                      select studentGroup;

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

Grade: 1
  Name: Alice
  Name: Charlie
Grade: 2
  Name: Bob
  Name: Eve
Grade: 3
  Name: David