派生类的 C# 转换

Question

一个菜鸟问题...

我有两个类，一个普通的(父)类和一个专门的(子)类:

public abstract class BaseTest
{
   public BaseTestSettings Settings{get;set;}
   public abstract void Run();
}

public class BaseTestSettings
{
   public double SettingsProp1{get;set;}
   public double SettingsProp1{get;set;}
}

public class SpecializaedTestSettings : BaseTestSettings
{
   public double SpecializaedTestSettingsPropA{get;set;}
   public double SpecializaedTestSettingsPropB{get;set;}
}

public class SpecializaedTest : BaseTest
{
   public SpecializaedTest()
   {
      this.Settings = new SpecializaedTestSettings();
   }

   public override void Run()
   {
      SpecializaedTestSettings settings = (SpecializaedTestSettings)this.Settings;
   }
}

有没有办法避免在专门测试中重写 Run 方法？我想一个解决方案是在 SpecializedTest 类中定义 SpecializedTestSettings 类型的 Settings 属性，但我的目标是避免这种情况并声明这些属性只有一次。我想我不能？

Answer 1

使用Generics :

public abstract class BaseTest<TSettings> where TSettings : BaseTestSettings
{
   public TSettings Settings{get;set;}
   public abstract void Run();
}

public class BaseTestSettings
{
   public double SettingsProp1{get;set;}
   public double SettingsProp1{get;set;}
}

public class SpecializaedTestSettings : BaseTestSettings
{
   public double SpecializaedTestSettingsPropA{get;set;}
   public double SpecializaedTestSettingsPropB{get;set;}
}

public class SpecializaedTest : BaseTest<SpecializaedTestSettings>
{
   public SpecializaedTest()
   {
      this.Settings = new SpecializaedTestSettings();
   }

   public override void Run()
   {
      SpecializaedTestSettings settings = this.Settings;
   }
}

如果您需要非泛型/协变版本，您可以编写协变接口(interface)或非泛型基类型。