C# 0 The Complete Reference

T

. It returns type 

T

 and takes an argument of type 

T

.

// A simple generic delegate.

using System;

// Declare a generic delegate.

delegate T SomeOp(T v);

class GenDelegateDemo {

  // Return the summation of the argument.

  static int Sum(int v) {

    int result = 0;

    for(int i=v; i>0; i--)

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      result += i;

    return result;

  }

  // Return a string containing the reverse of the argument.

  static string Reflect(string str) {

    string result = "";

    foreach(char ch in str)

      result = ch + result;

    return result;

  }

  static void Main() {

    // Construct an int delegate.

    SomeOp intDel = Sum;

    Console.WriteLine(intDel(3));

    // Construct a string delegate.

    SomeOp strDel = Reflect;

    Console.WriteLine(strDel("Hello"));

  }

}

The output is shown here:

6

olleH

Let’s look closely at this program. First, notice how the 

SomeOp

 delegate is declared:

delegate T SomeOp(T v);

Notice that 

T

 can be used as the return type even though the type parameter