如何在linq c#中透视对象列表和创建新列表？

// 假设有一个包含学生信息的对象列表
List<Student> students = new List<Student>
{
    new Student { Name = "Alice", Grade = "A", Age = 18 },
    new Student { Name = "Bob", Grade = "B", Age = 17 },
    new Student { Name = "Charlie", Grade = "A", Age = 19 },
    new Student { Name = "David", Grade = "C", Age = 18 },
    new Student { Name = "Emily", Grade = "B", Age = 17 }
};

// 使用LINQ查询表达式进行透视操作
var pivotQuery = from student in students
                 group student by student.Grade into g
                 select new
                 {
                     Grade = g.Key,
                     Count = g.Count(),
                     AverageAge = g.Average(s => s.Age)
                 };

// 使用LINQ方法语法进行透视操作
var pivotQuery = students.GroupBy(s => s.Grade)
                         .Select(g => new
                         {
                             Grade = g.Key,
                             Count = g.Count(),
                             AverageAge = g.Average(s => s.Age)
                         });

// 遍历透视结果并输出
foreach (var result in pivotQuery)
{
    Console.WriteLine($"Grade: {result.Grade}, Count: {result.Count}, Average Age: {result.AverageAge}");
}