csharp 设计图案结构代理

Posted 2021-05-12

using System;
 
namespace DoFactory.GangOfFour.Proxy.RealWorld
{
  /// <summary>
  /// MainApp startup class for Real-World 
  /// Proxy Design Pattern.
  /// </summary>
  class MainApp
  {
    /// <summary>
    /// Entry point into console application.
    /// </summary>
    static void Main()
    {
      // Create math proxy
      MathProxy proxy = new MathProxy();
 
      // Do the math
      Console.WriteLine("4 + 2 = " + proxy.Add(4, 2));
      Console.WriteLine("4 - 2 = " + proxy.Sub(4, 2));
      Console.WriteLine("4 * 2 = " + proxy.Mul(4, 2));
      Console.WriteLine("4 / 2 = " + proxy.Div(4, 2));
 
      // Wait for user
      Console.ReadKey();
    }
  }
 
  /// <summary>
  /// The 'Subject interface
  /// </summary>
  public interface IMath
  {
    double Add(double x, double y);
    double Sub(double x, double y);
    double Mul(double x, double y);
    double Div(double x, double y);
  }
 
  /// <summary>
  /// The 'RealSubject' class
  /// </summary>
  class Math : IMath
  {
    public double Add(double x, double y) { return x + y; }
    public double Sub(double x, double y) { return x - y; }
    public double Mul(double x, double y) { return x * y; }
    public double Div(double x, double y) { return x / y; }
  }
 
  /// <summary>
  /// The 'Proxy Object' class
  /// </summary>
  class MathProxy : IMath
  {
    private Math _math = new Math();
 
    public double Add(double x, double y)
    {
      return _math.Add(x, y);
    }
    public double Sub(double x, double y)
    {
      return _math.Sub(x, y);
    }
    public double Mul(double x, double y)
    {
      return _math.Mul(x, y);
    }
    public double Div(double x, double y)
    {
      return _math.Div(x, y);
    }
  }
}

using System;
 
namespace DoFactory.GangOfFour.Proxy.Structural
{
  /// <summary>
  /// MainApp startup class for Structural
  /// Proxy Design Pattern.
  /// </summary>
  class MainApp
  {
    /// <summary>
    /// Entry point into console application.
    /// </summary>
    static void Main()
    {
      // Create proxy and request a service
      Proxy proxy = new Proxy();
      proxy.Request();
 
      // Wait for user
      Console.ReadKey();
    }
  }
 
  /// <summary>
  /// The 'Subject' abstract class
  /// </summary>
  abstract class Subject
  {
    public abstract void Request();
  }
 
  /// <summary>
  /// The 'RealSubject' class
  /// </summary>
  class RealSubject : Subject
  {
    public override void Request()
    {
      Console.WriteLine("Called RealSubject.Request()");
    }
  }
 
  /// <summary>
  /// The 'Proxy' class
  /// </summary>
  class Proxy : Subject
  {
    private RealSubject _realSubject;
 
    public override void Request()
    {
      // Use 'lazy initialization'
      if (_realSubject == null)
      {
        _realSubject = new RealSubject();
      }
 
      _realSubject.Request();
    }
  }
}