如何在C＃中获取对象的子对象？

Question

在VB.net中，这段代码没问题：

Dim oPS as Object= CreateObject("Photoshop.Application.10")
Dim oDocument as Object= oPS.ActiveDocument

但在C＃中，此代码出现错误：

Object oPS = COMCreateObject("Photoshop.Application.10");
Object oDocument = oPS.ActiveDocument;

构建时出错

Error   2   'object' does not contain a definition for 'ActiveDocument' and no extension method 'ActiveDocument' accepting a first argument of type 'object' could be found (are you missing a using directive or an assembly reference?)

如何在C＃中获取对象的子对象（相同的vb.net）？

Answer 1

使用dynamic关键字代替object：

dynamic oPS = COMCreateObject("Photoshop.Application.10");
dynamic oDocument = oPS.ActiveDocument;

MSDN参考此处：https://msdn.microsoft.com/en-us/library/dd264736.aspx

Answer 2

在.net 4或更高版本中，您应该使用dynamic来实现此目的。这应该是：

var _type= Type.GetTypeFromProgID("Photoshop.Application.10");
dynamic inst= Activator.CreateInstance(_type);
inst.Visible = true;

Answer 3

为您的问题使用动态关键字。