C#泛型-Sort排序IComparer实现

using System;
using System.Collections.Generic;
/// <summary>
/// 学生类
/// </summary>
public class Student
{
    private string name;
    // 姓名
    public string Name
    {
        get { return name; }
        set { name = value; }
    }
    private int age;
    // 年龄
    public int Age
    {
        get { return age; }
        set { age = value; }
    }

    private string grade;
    // 年级
    public string Grade
    {
        get { return grade; }
        set { grade = value; }
    }
    //构造函数
    public Student(string name, int age, string grade)
    {
        this.name = name;
        this.age = age;
        this.grade = grade;
    }
    public override string ToString()
    {
        return this.name + "," + this.age.ToString() + "," + this.grade;
    }
}

public class StudentComparer : IComparer<Student>
{
    public enum CompareType
    {
        Name,
        Age,
        Grade
    }

    private CompareType type;
    // 构造函数，根据type的值，判断按哪个字段排序
    public StudentComparer(CompareType type)
    {
        this.type = type;
    }

    #region IComparer<Student> 成员
    public int Compare(Student x, Student y)
    {
        switch(this.type)
        {
            case CompareType.Name:
                return x.Name.CompareTo(y.Name);
            case CompareType.Age:
                return x.Age.CompareTo(y.Age);
            default://case CompareType.Grade:
                return x.Grade.CompareTo(y.Grade);
        }
    }

    #endregion
}

using System;
using System.Collections.Generic;
public class test
{
    public static void Main()
    {
        List<Student> arr = new List<Student>();
        arr.Add(new Student("张三", 7, "一年级"));
        arr.Add(new Student("李四", 11, "二年级"));
        arr.Add(new Student("王五", 21, "一年级"));
        arr.Add(new Student("陈六", 8, "三年级"));
        arr.Add(new Student("刘七", 15, "二年级"));
       
        // 调用Sort方法，实现按年级排序
        arr.Sort(new StudentComparer(StudentComparer.CompareType.Grade));       
        // 循环显示集合里的元素
        foreach( Student item in arr)
            Console.WriteLine(item.ToString());

        // 调用Sort方法，实现按姓名排序
        arr.Sort(new StudentComparer(StudentComparer.CompareType.Name));            
        // 循环显示集合里的元素
        foreach( Student item in arr)
            Console.WriteLine(item.ToString());
    }
}