C# 委托delegate用法示范

CalculateTax是一个委托，给定一个double值并返回一个double值

// CalculateTax is a delegate that takes a double and returns a double
public delegate double CalculateTax(double x);
static public double StateTax(double x) { 
   return x * 0.05; 
   }
static public double FederalTax(double x) { 
   if (x > 1000.0) 
      return x * 0.02; 
   else 
   return 0.0; 
}
static void Main(string[] args) {
CalculateTax stateDelegate = new CalculateTax(StateTax);
CalculateTax federalDelegate = new CalculateTax(FederalTax);
double amountOfPurchase = 12.99;
Console.WriteLine("{0}", stateDelegate(amountOfPurchase));
Console.WriteLine("{0}", federalDelegate(amountOfPurchase));
Console.In.ReadLine();
}