Question

我有一个抽象基类，我在扩展程序集中继承它。这是我的代码 region Contract Assembly



public interface IDummy
{
    int ForAbstractMethod();
    int ForVirtualMethod();
}

public abstract class BaseClass : IDummy
{
    public abstract int ForAbstractMethod();

    public virtual int ForVirtualMethod()
    {
        //Some base functionality
        return 0;
    }
}
#endregion

#region Extension Assembly

public class SomeExtension : BaseClass
{
    public override int ForAbstractMethod()
    {
        //I implement this method here, which is defined abstract in base class and this one works fine.
        return 100;
    }

    public override int ForVirtualMethod()
    {
        //Even though I override the virtual one here, still the one in the base class executes.
        return 1;
    }
}

#endregion


#region Main Program Assembly which references Contract Assembly

public class Program
{
    void Main()
    {
        //... compose catalog and other stuff

        IDummy dummy = someFactory.GetInstanceFromCatalog<IDummy>();//I get an instance
        int a = dummy.ForAbstractMethod();//this works as expected and returns 100
        a = dummy.ForVirtualMethod();//here I expect it to return 1 since I overrode it in child class, but it returns still 0.

        //...other stuff
    }
}

public interface IDummy { int ForAbstractMethod(); int ForVirtualMethod(); } public abstract class BaseClass : IDummy { public abstract int ForAbstractMethod(); public virtual int ForVirtualMethod() { //Some base functionality return 0; } } #endregion #region Extension Assembly public class SomeExtension : BaseClass { public override int ForAbstractMethod() { //I implement this method here, which is defined abstract in base class and this one works fine. return 100; } public override int ForVirtualMethod() { //Even though I override the virtual one here, still the one in the base class executes. return 1; } } #endregion #region Main Program Assembly which references Contract Assembly public class Program { void Main() { //... compose catalog and other stuff IDummy dummy = someFactory.GetInstanceFromCatalog<IDummy>();//I get an instance int a = dummy.ForAbstractMethod();//this works as expected and returns 100 a = dummy.ForVirtualMethod();//here I expect it to return 1 since I overrode it in child class, but it returns still 0. //...other stuff } }

我不知道覆盖虚拟和抽象方法之间是否存在任何差异，或者这是MEF的特定情况？谢谢你的帮助...

Answer 1

您未在ForVirtualMethod上声明BaseClass为虚拟广告。将其更改为此

public virtual int ForVirtualMethod()
{
    //Some base functionality
    return 0;
}

检查MSDN以获取有关虚拟成员声明的更多详细信息

virtual关键字用于修改方法，属性，索引器或事件声明，并允许在派生类中重写它。

在MEF类中重写虚拟方法的c＃不起作用

1 个答案: