Mega Code Archive
Illustrates the use of a delegate that calls object methods
<![CDATA[
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example12_3.cs illustrates the use of a delegate
that calls object methods
*/
using System;
// declare the DelegateCalculation delegate class
public delegate string DelegateDescription();
// declare the Person class
class Person
{
// declare two private fields
private string name;
private int age;
// define a constructor
public Person(string name, int age)
{
this.name = name;
this.age = age;
}
// define a method that returns a string containing
// the person's name and age
public string NameAndAge()
{
return(name + " is " + age + " years old");
}
}
// declare the Car class
class Car
{
// declare two private fields
private string model;
private int topSpeed;
// define a constructor
public Car(string model, int topSpeed)
{
this.model = model;
this.topSpeed = topSpeed;
}
// define a method that returns a string containing
// the car's model and top speed
public string MakeAndTopSpeed()
{
return("The top speed of the " + model + " is " +
topSpeed + " mph");
}
}
public class Example12_3
{
public static void Main()
{
// create a Person object named myPerson
Person myPerson = new Person("Jason Price", 32);
// create a delegate object that calls myPerson.NameAndAge()
DelegateDescription myDelegateDescription =
new DelegateDescription(myPerson.NameAndAge);
// call myPerson.NameAndAge() through myDelegateDescription
string personDescription = myDelegateDescription();
Console.WriteLine("personDescription = " + personDescription);
// create a Car object named myCar
Car myCar = new Car("MR2", 140);
// set myDelegateDescription to call myCar.MakeAndTopSpeed()
myDelegateDescription =
new DelegateDescription(myCar.MakeAndTopSpeed);
// call myCar.MakeAndTopSpeed() through myDelegateDescription
string carDescription = myDelegateDescription();
Console.WriteLine("carDescription = " + carDescription);
}
}
]]>