01.委托作为方法传递
using System; using static System.Console; namespace Mydelegate1 { //委托声明 public delegate bool ComparsionHandler(int first,int second); class Program { static void Main(string[] args) { int[] sum = new[] {5, 10, 2, 0, 40, 6, 9, 8}; BubbleSort(sum, GreaterThan); foreach (var item in sum) { WriteLine(item); } ReadKey(); } //委托作为方法传递 public static void BubbleSort(int[] items,ComparsionHandler comparsionMethod) { int i ; int j ; int temp; for (i = items.Length - 1; i >=0; i--) { for (j = 1; j <=i ; j++) { if (comparsionMethod(items[j-1],items[j])) { temp = items[j - 1]; items[j - 1] = items[j]; items[j] = temp; } } } } public static bool GreaterThan(int first, int second) { return first > second; } } }02. 03.Lambda表达式
//委托声明 public delegate bool ComparsionHandler(int first, int second); class Program { static void Main(string[] args) { int[] sum = new[] { 5, 10, 2, 0, 40, 6, 9, 8 }; //整数 first和整数 second 用于 返回 first大于second的结果 BubbleSort(sum, (int first, int second) => { return first >second;}); //BubbleSort(sum, (int first, int second) => first > second); foreach (var item in sum) { WriteLine(item); } ReadKey(); } //委托作为方法传递 public static void BubbleSort(int[] items, ComparsionHandler comparsionMethod) { int i; int j; int temp; for (i = items.Length - 1; i >= 0; i--) { for (j = 1; j <= i; j++) { if (comparsionMethod(items[j - 1], items[j])) { temp = items[j - 1]; items[j - 1] = items[j]; items[j] = temp; } } } } }04.通用的委托
namespace Mydelegate5 { public delegate void Action<T>(T arg); class Program { public Func<int,float> func; static void Main(string[] args) { Program p=new Program(); p.func = Sum; WriteLine(p.func(10)); //10 ReadKey(); } static float Sum(int a) { return a; } } }05.多播委托 和空值传播运算符
using System; using static System.Console; namespace Event02 { class Program { static void Main(string[] args) { Thermostat thermostat=new Thermostat(); Cooler cooler=new Cooler(60); Heater heater=new Heater(80); thermostat.OnTemperatureChanged += cooler.OnTemperatureChanged; thermostat.OnTemperatureChanged += heater.OnTemperatureChanged; while (true) { thermostat.CurrentTemperature = float.Parse(ReadLine()); } ReadKey(); } } //发布者 class Thermostat { public Action<float> OnTemperatureChanged { get; set;} private float _CurrentTemperature; public float CurrentTemperature { get => _CurrentTemperature; set { if (value!=CurrentTemperature) { _CurrentTemperature = value; OnTemperatureChanged?.Invoke(value); } } } } //加热器 class Cooler { public float Temperature { get; set; } //温度 public Cooler(float temperature) { this.Temperature = temperature; } public void OnTemperatureChanged(float newTemperature) { if (newTemperature>Temperature) { WriteLine("Cooler:ON"); } else { WriteLine("Cooler:Off"); } } } //冷却器 class Heater { public float Temperature { get; set; } //温度 public Heater(float temperature) { this.Temperature = temperature; } public void OnTemperatureChanged(float newTemperature) { if (newTemperature <Temperature) { WriteLine("Heater:ON"); } else { WriteLine("Heater:Off"); } } } }