装饰模式
代码
// Decorator pattern -- Structural example
using System;
// "Component"
abstract class Component
{
// Methods
abstract public void Operation();
}
// "ConcreteComponent"
class ConcreteComponent : Component
{
// Methods
override public void Operation()
{
Console.WriteLine("ConcreteComponent.Operation()");
}
}
// "Decorator"
abstract class Decorator : Component
{
// Fields
protected Component component;
// Methods
public void SetComponent( Component component )
{
this.component = component;
}
override public void Operation()
{
if( component != null )
component.Operation();
}
}
// "ConcreteDecoratorA"
class ConcreteDecoratorA : Decorator
{
// Fields
private string addedState;
// Methods
override public void Operation()
{
base.Operation();
addedState = "new state";
Console.WriteLine("ConcreteDecoratorA.Operation()");
}
}
// "ConcreteDecoratorB"
class ConcreteDecoratorB : Decorator
{
// Methods
override public void Operation()
{
base.Operation();
AddedBehavior();
Console.WriteLine("ConcreteDecoratorB.Operation()");
}
void AddedBehavior()
{
}
}
/**//// <summary>
/// Client test
/// </summary>
public class Client
{
public static void Main( string[] args )
{
// Create ConcreteComponent and two Decorators
ConcreteComponent c = new ConcreteComponent();
ConcreteDecoratorA d1 = new ConcreteDecoratorA();
ConcreteDecoratorB d2 = new ConcreteDecoratorB();
// Link decorators
d1.SetComponent( c );
d2.SetComponent( d1 );
d2.Operation();
Console.ReadLine();
}
}
using System;
// "Component"
abstract class Component
{
// Methods
abstract public void Operation();
}
// "ConcreteComponent"
class ConcreteComponent : Component
{
// Methods
override public void Operation()
{
Console.WriteLine("ConcreteComponent.Operation()");
}
}
// "Decorator"
abstract class Decorator : Component
{
// Fields
protected Component component;
// Methods
public void SetComponent( Component component )
{
this.component = component;
}
override public void Operation()
{
if( component != null )
component.Operation();
}
}
// "ConcreteDecoratorA"
class ConcreteDecoratorA : Decorator
{
// Fields
private string addedState;
// Methods
override public void Operation()
{
base.Operation();
addedState = "new state";
Console.WriteLine("ConcreteDecoratorA.Operation()");
}
}
// "ConcreteDecoratorB"
class ConcreteDecoratorB : Decorator
{
// Methods
override public void Operation()
{
base.Operation();
AddedBehavior();
Console.WriteLine("ConcreteDecoratorB.Operation()");
}
void AddedBehavior()
{
}
}
/**//// <summary>
/// Client test
/// </summary>
public class Client
{
public static void Main( string[] args )
{
// Create ConcreteComponent and two Decorators
ConcreteComponent c = new ConcreteComponent();
ConcreteDecoratorA d1 = new ConcreteDecoratorA();
ConcreteDecoratorB d2 = new ConcreteDecoratorB();
// Link decorators
d1.SetComponent( c );
d2.SetComponent( d1 );
d2.Operation();
Console.ReadLine();
}
}