1、接口中的方法并不实现具体功能,继承于该接口的类必须实现具体功能。
核心思想:对修改封闭,对扩展开放。
2、Sort()方法:
默认:Sort(内容)
英文:按照首字母顺序排序,首字母相同则看第二个字母;
数字:从小到大排序;
自定义 Sort(内容,排序规则)
内容按照自定义的规则排序。
host类
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleEnum { class host { [STAThread] static void Main(string[] args) { // 创建一个数组,里面放汽车名和年份 car[] arrayOfCars = new car[6] { new car("Ford",1992), new car("Fiat",1988), new car("Buick",1932), new car("Ford",1932), new car("Dodge",1999), new car("Honda",1977) }; Console.WriteLine("排序前 "); foreach (car c in arrayOfCars) Console.WriteLine(c.Make + " " + c.Year); Console.WriteLine("Sort默认正向排序 "); Array.Sort(arrayOfCars); foreach (car c in arrayOfCars) Console.WriteLine(c.Make + " " + c.Year);
Console.WriteLine("Sort 按年份正向排序 ) "); Array.Sort(arrayOfCars, car.sortYearAscending()); foreach (car c in arrayOfCars) Console.WriteLine(c.Make + " " + c.Year); Console.WriteLine("Sort 按汽车名正向排序 "); Array.Sort(arrayOfCars, car.sortMakeDescending()); foreach (car c in arrayOfCars) Console.WriteLine(c.Make + " " + c.Year); Console.WriteLine("Sort 按汽车名反向排序 "); Array.Sort(arrayOfCars, car.sortYearDescending()); foreach (car c in arrayOfCars) Console.WriteLine(c.Make + " " + c.Year); Console.ReadLine(); } } }
Car类
using System; using System.Collections; namespace ConsoleEnum { public class car : IComparable { // 嵌套类:类中的类。 // 按年升序 private class sortYearAscendingHelper : IComparer { //实现接口定义的方法 int IComparer.Compare(object a, object b) { car c1 = (car)a; car c2 = (car)b; if (c1.year > c2.year) return 1; if (c1.year < c2.year) return -1; else return 0; } } // 按年降序 private class sortYearDescendingHelper : IComparer { //实现接口定义的方法 int IComparer.Compare(object a, object b) { car c1 = (car)a; car c2 = (car)b; if (c1.year < c2.year) return 1; if (c1.year > c2.year) return -1; else return 0; } } // 按汽车名字母降序 private class sortMakeDescendingHelper : IComparer { //实现接口定义的方法 int IComparer.Compare(object a, object b) { car c1 = (car)a; car c2 = (car)b; return String.Compare(c2.make, c1.make); } } private int year; private string make; //构造函数 public car(string Make, int Year) { make = Make; year = Year; } //属性 public int Year { get { return year; } set { year = value; } } public string Make { get { return make; } set { make = value; } } // 实现IComparable接口来提供默认的排序顺序的对比。 public int IComparable.CompareTo(object obj) { car c = (car)obj;
//调用了C#中封装的类,详情见下一篇 return String.Compare(this.make, c.make); }
//因为这里使用了嵌套类,把嵌套类包裹到方法中方便调用(类名.方法名) public static IComparer sortYearAscending() {
//调用了上面的类 return (IComparer)new sortYearAscendingHelper(); } public static IComparer sortYearDescending() {
//调用了上面的类 return (IComparer)new sortYearDescendingHelper(); } public static IComparer sortMakeDescending() {
//调用了上面的类 return (IComparer)new sortMakeDescendingHelper(); } } }