看书时这段话看不懂！谁能跟我讲一下！ But also recall that your COM object can be a local (out-of-process) server in separate EXE address spaces, or even accessed remotely. Any time you need to pass a pointer to a COM method in such an object, you're got a problem: the pointer is meaningless in any other address space. What's meaningful is the data to which the pointer points. This data has to be copied into the other address space—and perhaps back. This process of copying the right data is called marshalling. Thankfully, COM does the marshalling for you in most cases. But in order for it to do so, you need to tell it more than just the type the pointer points to—you need to tell COM how the pointer is used. For instance, does the pointer point to an array? A string? Is the parameter an input parameter only? An output parameter? Both? You can see that there's no way to express this in C++.
放在满足客户的要求就行了。