在C＃中标记有ComVisible特性的类接口继承 [英] Interface inheritance in ComVisible classes in C#

问题描述

继承财产（P1）是不是从W / CSCRIPT accessable。

Inherited property (P1) is not accessable from w/cscript.

类的结构看起来是这样的：

Class structure looks something like this :

[ComVisible]
public interface IA 
{
     string P1{get;} 
} 

[ComVisible]
public interface IB : IA
{
    string P2{get;} 
}

[ComVisible]
public abstract class Base : IA
{
    public string P1{get{return "somestring";}}
}   

[ComVisible]
public class Concrete : Base, IB
{
   public string P2{get{return "P2somestring";}}
}

客户端代码：

try{
var obj = new ActiveXObject("Concrete");
WshShell.Popup(obj.P1); //<-- displays empty string
}catch(e)
{
WshShell.Popup(e.description);
}

如果我添加属性P1接口IB，一切工作正常，
，而什么传承然后点？还是我在这里做的东西真的错了？

if i add property P1 to interface IB, everything works fine, but whats the point of inheritance then? Or am i doing here something really wrong?

推荐答案

我偷了这个问题的答案从的 COM互操作：基本类的属性不会暴露给出COM 链接非常类似的问题C＃暴露在COM - 接口继承

I'm stealing the answer to this from the COM Interop: Base class properties not exposed to COM link given in the very similar question "C# exposing to COM - interface inheritance"

在特别在该网站上的MVP指出：

In particular the MVP on that site states:

在COM接口可以相互继承。然而，公开的.NET接口，COM的.NET实现不支持继承。因此，你必须复制在基本界面任何接口成员派生的接口......建立暴露COM接口时，互操作的代码不看基本接口类型。

In COM interfaces can inherit from one another. However the .NET implementation that exposes the .NET interface to COM does not support inheritance. Therefore you must replicate any interface members in a base interface to the derived interface... The interop code does not look at base interface types when building the exposed COM interface.

它确实提出了一些解决方法，比如从两个接口继承，或实施一个'本土'的TLB（写inteface在IDL和MIDL编译 - 应该有这可见工作室项目）

It does suggest some workarounds, such as inheriting from both interfaces, or implementing a 'native' TLB (write the inteface in IDL and compile it with MIDL - there should be projects for this in vis studio).

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