观察者模式的定义
一个目标物件管理所有相依于它的观察者物件, 并且在它本身的状态改变时主动发出通知
.Net Core实现观察者模式的代码
Person.cs
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| using System;
namespace ObserverPattern
{
public class Person
{
public event EventHandle<FallsIllEventArgs> FallsIll;
public void OnFallsIll()
{
FallsIll?.Invoke(this, new FallsIllEventArgs("China Beijing"));
}
}
}
|
FallsIllEventArgs.cs
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| using System;
namespace ObserverPattern
{
public readonly string Address;
public FallsIllEventArgs(string address)
{
this.Address = address;
}
}
|
Program.cs
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| using System;
namespace ObserverPattern
{
class Program
{
static void Main(string[] args)
{
var person = new Person();
person.FallsIll += OnFallsIll;
person.OnFallsIll();
person.FallsIll -= OnFallsIll;
}
private static void OnFallsIll(object sender, FallsIllEventArgs eventArgs)
{
Console.WriteLine($'A doctor has been called to(eventArgs.Address)');
}
}
}
|