C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace 数组排序
{
    /// <summary>
    /// IComparable : 接口
    /// </summary>
    public class Student : IComparable
    {
        public int ID { get; set; }
        public string Name { get; set; }
        public int Age { get; set; }

        /// <summary>
        /// 重写ToString方法
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return String.Format("ID={0} 	 Name={1} 	 Age={2}", this.ID, this.Name, this.Age);
        }

        /// <summary>
        /// 实现IComparable接口的CompareTo()方法来通过【Age】来进行排序
        /// </summary>
        /// <param name="obj"></param>
        /// <returns>1:大于 -1:小于 0:等于</returns>
        public int CompareTo(object obj)
        {
            Student student = (Student)obj;
            if ( this.Age > student.Age)
            {
                return 1;
            }
            if (this.Age < student.Age)
            {
                return -1;
            }
            return 0;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Student[] student = 
            {
                new Student(){ID = 001, Name = "张三", Age = 15},
                new Student(){ID = 002, Name = "李四", Age = 16},
                new Student(){ID = 003, Name = "王五", Age = 18},
                new Student(){ID = 004, Name = "赵六", Age = 14}
            };

            //Console.WriteLine(student);     // 打印结果: 数组排序.Student[]
            //Console.WriteLine(student[1]);    // 打印结果: ID=002, Name="李四", Age=16
            
            Console.WriteLine("student数组未进行排序前:");
            for (int i = 0; i < student.Length; ++i )
            {
                Console.WriteLine("student[{0}] : {1}", i, student[i]);
            }
            
            /// Array.Sort():数组的静态方法:默认升序排列
            Array.Sort(student);
            Console.WriteLine("
=================按照【Age】升序排序后===================");
            foreach (var v in student)
            {
                Console.WriteLine(v); //默认调用Student的ToString()方法
            }

            /// Array.Reverse()方法:反转整个一维数组的元素顺序
            /// 如果要实现【降序】排列,则必须先通过Array.Sort(数组)的方法先将数组按升序有序排列后,再
            /// 调用Array.Reverse()方法反转数组的元素,实现降序排列.
            /// 如果要实现自定义类型的数组排序,则必须要
            Array.Reverse(student);
            Console.WriteLine("
=================按照【Age】降序排序后===================");
            foreach (Student st in student)
            {
                Console.WriteLine(st);
            }

            Console.ReadLine();
        }
    }
}