public Main()
{
//create the subject
var s1 = new ConcreteSubject();
//version 1 -
//create the observer
//the data is passed during notification.
var o3 = new ConcreteObserver();
var o4 = new ConcreteObserver();
//version 2 -
//create the observer and pass the subject
//to pull the requiered data after a change.
var o1 = new ConcreteObserver(s1);
var o2 = new ConcreteObserver(s1);
//Attach observers , only version 1
s1.Add(o3);
s1.Add(o4);
//Perform a change of state.
s1.ID = 1;
s1.ID = 3;
}
static void Main(string[] args)
{
var s = new Subject();
IObserver a = new ConcreteObserver("Observer A");
IObserver b = new ConcreteObserver("Observer B");
IObserver c = new ConcreteObserver("Observer C");
s.RegisterObserver(a);
s.RegisterObserver(b);
s.RegisterObserver(c);
Console.WriteLine("Registered 3 observer...");
Console.WriteLine("Notify all observer:");
s.NotifyObservers("Hello observers!");
Console.WriteLine();
s.UnregisterObserver(b);
Console.WriteLine("Removed observer B...");
s.NotifyObservers("Hello observers!");
Console.WriteLine();
Console.ReadKey();
}
public void Send2Signals_WithSomeClient_MustBeUpdateAtSecondSignal()
{
var testSubject = new ConcreteSubject()
{
SubjectState = "signal1"
};
var observer1 = new ConcreteObserver(testSubject, "observer1");
var observer2 = new ConcreteObserver(testSubject, "observer2");
var observer3 = new ConcreteObserver(testSubject, "observer3");
testSubject.Attach(observer1);
testSubject.Attach(observer2);
testSubject.Attach(observer3);
testSubject.Notify();
Assert.Equal("signal1", observer1.GetState());
Assert.Equal("signal1", observer2.GetState());
Assert.Equal("signal1", observer2.GetState());
testSubject.SubjectState = "signal2";
testSubject.Notify();
Assert.Equal("signal2", observer1.GetState());
Assert.Equal("signal2", observer2.GetState());
Assert.Equal("signal2", observer2.GetState());
}
static void Main()
{
IObserver observer = new ConcreteObserver();
Subject subject = new Subject();
subject.Regist(observer);
subject.Notify();
}
static void Main()
{
ConcreteSubject subject = new ConcreteSubject();
IObserver observer = new ConcreteObserver(subject);
subject.ChangeSubjectValue(50);
}
public void ObserverTest1()
{
ConcreteSubject subject = new ConcreteSubject();
ConcreteObserver observer1 = new ConcreteObserver();
subject.Attach(observer1);
Assert.True(observer1.Notified == 0);
}
void Start()
{
var subject = new ConcreteSubject();
var observer = new ConcreteObserver(subject);
subject.Attach(observer);
subject.SetState("测试");
}
// Use this for initialization
void Start()
{
ConcreteSubject subject = new ConcreteSubject();
Observer observer = new ConcreteObserver();
subject.AddObserver(observer);
subject.State = "下雨";
subject.State = "下雪";
}
static void Main(string[] args)
{
ConcreteSubject subject = new ConcreteSubject();
Observer observer = new ConcreteObserver("张三", subject);
subject.Attach(observer);
subject.SubjectState = "老板回来了";
subject.Notify();
}
public void SimpleTest()
{
ConcreteSubject subject = new ConcreteSubject();
ConcreteObserver observer1 = new ConcreteObserver(subject);
ConcreteObserver observer2 = new ConcreteObserver(subject);
ConcreteObserver observer3 = new ConcreteObserver(subject);
subject.Action();
}
public void ObserverDemo()
{
var subject = new ConcreteSubject();
var o = new ConcreteObserver();
var o2 = new ConcreteObserver2();
subject.Attach(o);
subject.Attach(o2);
subject.DoSomething();
}
public void GivenAnyObservableBusiness_WhenDoBusinessStuff_ThenObserverGetNotified()
{
// Arrange
var observableBusiness = new BusinessClassObservable();
var observer = new ConcreteObserver("Observer");
// Act
observableBusiness.DoBusinessStuff();
// Assert
observableBusiness.ObservableState.Should().Be(observer.ObservableState);
}
public void observerColor()
{
ConcreteSubject subject = new ConcreteSubject();
subject.brush = Brushes.Red;
Ellipse testEll1 = new Ellipse();
ConcreteObserver ob1 = new ConcreteObserver(subject, testEll1);
subject.Attach(ob1);
subject.Notify();
Assert.AreEqual(testEll1.Fill, Brushes.Red);
}
public void Initialize()
{
cs = new ConcreteSubject();
co1 = new ConcreteObserver(cs);
co2 = new ConcreteObserver(cs);
co3 = new ConcreteObserver(cs);
cs.Attach(co1);
cs.Attach(co2);
cs.Attach(co3);
}
public void ObserverTest3()
{
ConcreteSubject subject = new ConcreteSubject();
ConcreteObserver observer1 = new ConcreteObserver();
ConcreteObserver observer2 = new ConcreteObserver();
subject.Attach(observer1);
subject.Notify();
subject.Attach(observer2);
subject.Notify();
Assert.True((observer1.Notified == 2) && (observer2.Notified == 1));
}
public void subjectCount()
{
ConcreteSubject subject = new ConcreteSubject();
Ellipse testEll1 = new Ellipse();
ConcreteObserver ob1 = new ConcreteObserver(subject, testEll1);
Ellipse testEll2 = new Ellipse();
ConcreteObserver ob2 = new ConcreteObserver(subject, testEll2);
subject.Attach(ob1);
subject.Attach(ob2);
Assert.AreEqual(subject.observers.Count, 2);
}
public void Observer_Pattern_Test()
{
var subject = new Subject();
var observer = new ConcreteObserver();
subject.Attach(observer);
Assert.IsTrue(observer.IsActive);
subject.ChangeStates();
Assert.IsFalse(observer.IsActive);
}
public void ObserverTest4()
{
ConcreteSubject subject = new ConcreteSubject();
ConcreteObserver observer1 = new ConcreteObserver();
ConcreteObserver observer2 = new ConcreteObserver();
subject.Attach(observer1);
subject.Notify(subject);
subject.Attach(observer2);
subject.Notify(subject);
subject.Detach(observer1);
subject.Notify(subject);
Assert.True(observer1.Notified == observer2.Notified);
}
private static void Main()
{
var subject = new ConcreteSubject();
var observer1 = new ConcreteObserver("observer1");
var observer2 = new ConcreteObserver("observer2");
subject.Attach(observer1);
subject.Attach(observer2);
subject.SubjectState = "Modified";
subject.Detach(observer1);
subject.Detach(observer2);
subject.SubjectState = "Modified Again !";
Console.ReadKey();
}
static void Main(string[] args)
{
Engine engine = new Engine();
Consumer consumer = new Consumer("consumer1", engine);
Consumer consumer2 = new Consumer("consumer2", engine);
engine.SwitchGear();
consumer.Unsubscribe();
engine.SwitchGear();
Console.WriteLine("");
Console.WriteLine("============ Structural patterns (realize relationships between entities) ============");
Console.WriteLine("~~~~~~~~~~~~~ Facade (A single class that represents an entire subsystem) ~~~~~~~~~~~~~");
Structural.Facade facade = new Structural.Facade();
facade.AddMethod();
Console.WriteLine("~~~~~~~~~~~~~ Decorator (Attach additional responsibilities to an object dynamically) ~~~~~~~~~~~~~");
ConcreteDecorator decorator = new ConcreteDecorator();
ConcreteComponent concreteComponent = new ConcreteComponent();
decorator.SetComponent(concreteComponent);
decorator.Operation();
Console.WriteLine("");
Console.WriteLine("============ Behavioral patterns (communications between entities) ============");
Console.WriteLine("~~~~~~~~~~~~~ Observer (when one object changes state, all its dependents are notified and updated automatically) ~~~~~~~~~~~~~");
ConcreteSubject subject = new ConcreteSubject();
ConcreteObserver observer = new ConcreteObserver(subject, "X");
subject.Attach(observer);
// Change subject and notify observers
subject.State = "ABC";
subject.Notify();
Console.WriteLine("~~~~~~~~~~~~~ Strategy (Define a family of algorithms, encapsulate each one, and make them interchangeable) ~~~~~~~~~~~~~");
Context context = new Context(new SortStrategy1());
context.ContextSortInterface();
context = new Context(new SortStrategy2());
context.ContextSortInterface();
Console.WriteLine("============ Structural patterns ============");
Console.WriteLine("~~~~~~~~~~~~~ Singleton (Ensure a class has only one instance and provide a global point of access to it) ~~~~~~~~~~~~~");
Cache instance1 = Cache.Instance();
Cache instance2 = Cache.Instance();
Console.WriteLine("instance1 == instance2? {0}", instance1 == instance2);
Console.WriteLine("~~~~~~~~~~~~~ FactoryMethod ~~~~~~~~~~~~~");
IComponent component = Creator.Create("first");
}
//LD_OBSERVER_000
public static void RunObserverBehavioralPattern()
{
//one subject and two observers
ISubject <string> subject = new ConcreteSubject <string>();
ObserverBehavioralPattern.IObserver <string> observer1 = new ConcreteObserver <string>("observer1");
ObserverBehavioralPattern.IObserver <string> observer2 = new ConcreteObserver <string>("observer2");
//register the observers to the subject
subject.Attach(observer1);
subject.Attach(observer2);
//a change to the subject automatically notifies all the observers
subject.SetState("stateX");
}
public void TestMethod1()
{
var subject = new ConcreteSubject();
var observer1 = new ConcreteObserver(subject);
var observer2 = new ConcreteObserver(subject);
subject.Attach(observer1);
subject.Attach(observer2);
subject.State = "NEW";
subject.Notify();
Assert.AreEqual(subject.State, observer1.State);
Assert.AreEqual(subject.State, observer2.State);
}
public static void Observer()
{
ConcreteSubject cs = new ConcreteSubject();
ConcreteObserver co1 = new ConcreteObserver("Observer 1");
ConcreteObserver co2 = new ConcreteObserver("Observer 2");
ConcreteObserver co3 = new ConcreteObserver("Observer 3");
cs.Add(co1);
cs.Add(co2);
cs.Add(co3);
cs.Notify();
Console.Read();
}
public void Run()
{
ConcreteSubject subject = new ConcreteSubject();
Observer observer1 = new ConcreteObserver(subject, "X");
Observer observer2 = new ConcreteObserver(subject, "Y");
Observer observer3 = new ConcreteObserver(subject, "Z");
subject.RegisterObservers(observer1, observer2, observer3);
// Change subject and notify observers
subject.SubjectState = "ABC";
subject.UnRegisterObservers(observer1, observer3);
subject.SubjectState = "XYZ";
Console.WriteLine("\nImplementation using .NET IObserver and IObservable");
DotNetImplementation.NetObserver.Run();
}
public void Start()
{
var subject = new ConcreteSubject();
var firstConcreteObserver = new ConcreteObserver(subject, "First");
var secondConcreteObserver = new ConcreteObserver(subject, "Second");
subject.Attach(firstConcreteObserver);
subject.Attach(secondConcreteObserver);
subject.SubjectState = "FirstState";
subject.Notify();
subject.Detach(secondConcreteObserver);
subject.SubjectState = "SecondState";
subject.Notify();
}
private static void Main()
{
using (var subject = new ConcreteSubject())
{
var observer1 = new ConcreteObserver("observer1");
var observer2 = new ConcreteObserver("observer2");
using (subject.Subscribe(observer1))
using (subject.Subscribe(observer2))
{
subject.SubjectState = "Modified";
}
subject.SubjectState = "Modified Again !";
}
Console.ReadKey();
}
public ObserverPattern()
{
ConcreteSubject subject = new ConcreteSubject();
ConcreteObserver observer1 = new ConcreteObserver("Rome", subject);
ConcreteObserver observer2 = new ConcreteObserver("Paris", subject);
ConcreteObserver observer3 = new ConcreteObserver("London", subject);
subject.Attach(observer1);
subject.Attach(observer2);
subject.Attach(observer3);
for (int i = 0; i < 10; i++)
{
subject.ChangeState($"Status #{i}");
subject.Notify();
Thread.Sleep(500);
}
}
static void Main(string[] args)
{
var concreteSubject = new ConcreteSubject();
var observer1 = new ConcreteObserver("Observer 1");
var observer2 = new ConcreteObserver("Observer 2");
concreteSubject.ConcreteSubjectState = 2;
concreteSubject.Attach(observer1);
observer1.Update(concreteSubject);
concreteSubject.Attach(observer2);
observer2.Update(concreteSubject);
concreteSubject.ConcreteSubjectState = 3;
concreteSubject.Detach(observer1);
concreteSubject.ConcreteSubjectState = 4;
}
static void Main(string[] args)
{
//Create a Product with Out Of Stock Status
ConcreteSubject RedMI = new ConcreteSubject("Red MI Mobile", 10000, "Out Of Stock");
//User Anurag will be created and user1 object will be registered to the subject
ConcreteObserver user1 = new ConcreteObserver("Anurag", RedMI);
//User Pranaya will be created and user1 object will be registered to the subject
ConcreteObserver user2 = new ConcreteObserver("Pranaya", RedMI);
//User Priyanka will be created and user3 object will be registered to the subject
ConcreteObserver user3 = new ConcreteObserver("Priyanka", RedMI);
Console.WriteLine("Red MI Mobile current state : " + RedMI.GetAvailability());
Console.WriteLine();
// Now product is available
RedMI.SetAvailability("Available");
Console.Read();
}
public void destroyConcreteObserver(ConcreteObserver o)
{
activeConcreteObserver.Remove(o);
}