delegate void IntMethodInvoker(int x);//必须提供方法的签名和返回类型等细节，类型安全性非常高

private delegate string GetString();
static void Main()
{int x = 40;GetAString firstStringMethod = new GetAString(x.ToString);//ToString()是实例方法（不是静态），因此需要指定实例x和方法名来正确地使用委托
    ...
}

Console.WriteLine("String is {0}",firstStringMethod());
//等价于
//Console.WriteLine("String is{0}",x.ToString());

GetAString firstStringMethod = x.ToString;

delegate double DoubleOp(double x);
static void Main()
{DoubleOp[] operations = {MathOperations.MultipleByTwo,MathOperations.Square};...
}

delegate double DoubleOp(double x);Func<double,double>[] operations = {MathOperations.MultipleByTwo,MathOperations.Square};

private static void ProcessAndDisplayNumber(Func<double, double> action, double value)
{double result = action(value);Console.WriteLine("Value is {0},result of operation is {1}", value, result);
}

/// <summary>
/// 冒泡排序的泛型版本
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="sortArray"></param>
/// <param name="comparison"></param>
static public void Sort<T>(IList<T> sortArray, Func<T, T, bool> comparison)
{bool swapped = true;do{swapped = false;for (int i = 0; i < sortArray.Count - 1; i++){if (comparison(sortArray[i + 1], sortArray[i])){T temp = sortArray[i];sortArray[i] = sortArray[i + 1];sortArray[i + 1] = temp;swapped = true;}}} while (swapped);
}

Action<double> operations = MathOperations.MultiplyByTwo;
operations += MathOperations.Square;

static void Main()
{Action d1 = One;d1 += Two;Delegate[] delegates = d1.GetInvocationList();//返回委托数组foreach(Action d in delegates){try{d();}catch(Exception){Console.WriteLine("Exception caught");}}
}

string mid = ",middle part,";Func<string,string> anonDel = delegate(string param)
{param += mid;param += " and this was added to the string.";return param;
};
Console.WriteLine(anonDel("Start of string"));

string mid = ",middle part,";Func<string,string> anonDel = param =>
{param += mid;param += " and this was added to the string.";return param;
};
Console.WriteLine(anonDel("Start of string"));

Func<string,string> oneParam = s => String.Format("change uppercase {0}",s.ToUpper());//单参

Func<double,double,double> TwoParams = (x,y) => x*y;//多参

Func<double,double,double> twoParamsWithTypes = (double x,double y) => x*y;//添加参数类型

namespace Wrox.ProcSharp.Delegates
{//事件发布程序public class CarInfoEventArgs : EventArgs{public CarInfoEventArgs(string car){this.Car = car;}public string Car{get;private set;}}public class CarDealer{public event EventHandler<CarInfoEventArgs> NewCarInfo;public void NewCar(string car){Console.WriteLine("CarDealer, new car{0}", car);if(NewCarInfo != null){NewCarInfo(this, new CarInfoEventArgs(car));}}}//事件监听器public class Consumer{private string name;public Consumer(string name){this.name = name;}public void NewCarIsHere(object sender,CarInfoEventArgs e){Console.WriteLine("{0}：car{1} is new",name,e.Car);}}//订阅class Program{static void Main(){var dealer = new CarDealer();    var michael = new Consumer("Michael");dealer.NewCarInfo += michael.NewCarIsHere;dealer.NewCar("Mercedes");}}
}

View Code

public event EventHandle<TEventArgs>(object sender,TEventArgs e) where TEventArgs:EventArgs

public event EventHandler<CarInfoEventArgs> NewCarInfo;

private delegate EventHandler<CarInfoEventArgs> newCarInfo;
public event EventHandler<CarInfoEventArgs> NewCarInfo
{add{newCarInfo += value;}remove{newCarInfo = value;}
}