c# - C#中从基类调用重写的方法

Question

给定以下 C# 类定义和代码:

public class BaseClass
{
    public virtual void MyMethod()
    {
        ...do something...
    }
}

public class A : BaseClass
{
    public override void MyMethod()
    {
        ...do something different...
    }
}

public class B : BaseClass
{
    public override void MyMethod()
    {
        ...do something different...
    }
}

public class AnotherObject
{
    public AnotherObject(BaseClass someObject)
    {
        someObject.MyMethod(); //This calls the BaseClass method, unfortunately.
    }
}

我想调用在 A 或 B 中实际找到的 MyMethod()，假设传入的对象实际上是 A 或 B 的实例，而不是在 基类。缺少做这样的事情:

public class AnotherObject
{
    public AnotherObject(BaseClass someObject)
    {
        A temp1 = someObject as A;
        if (A != null)
        {
            A.MyMethod();
        }
        
        B temp2 = someObject as B;
        if (B != null)
        {
            B.MyMethod();
        }
    }
}

我该怎么做？

Answer 1

调用哪个方法是通过传递给 AnotherObject 构造函数的类型的多态性来确定的:

AnotherObject a = new AnotherObject(new A()); // invokes A.MyMethod() 
AnotherObject b = new AnotherObject(new B()); // invokes B.MyMethod() 
AnotherObject c = new AnotherObject(new BaseClass()); //invokes BaseClass.MyMethod()