怪事！接口与抽象类的问题？不知各位能否解决？

[developerworks]

问题如下：
C#代码运行正常
====================================================================
public interface Class1
{
bool IsClosed{get;}
}
public abstract class Class2:Class1
{
public abstract bool IsClosed{get;}

}
====================================================================
VB.net代码出错
Public Interface t1
ReadOnly Property abc() As Boolean
End Interface

Public MustInherit Class t2
Implements t1
Public MustOverride ReadOnly Property abc() As Boolean
End Class

错误信息：
test3.t2”必须为接口“test3.t1”实现“ReadOnly Property abc() As Boolean”。实现属性必须有匹配的“ReadOnly”/“WriteOnly”说明符。

[Jackboy]

正确的代码如下:

Public Interface t1
ReadOnly Property abc() As Boolean
End Interface

Public MustInherit Class t2
Implements t1
Public MustOverride ReadOnly Property abc() As Boolean Implements t1.abc
End Class