问题
I have an exported function from a dll written in c++ with the following signiture:
Foo( LPSTREAM *pStream, UINT &Size )
that returns an memory stream and obviously its size. What I am having difficulties with is creating a signiture for the exported function and then attempting to read the stream in C#. At one point was able to use "unsafe" byte pointer to get the information, but this does not fit our requirements.
Any thoughts, examples, samples etc would be greatly appreciated.
回答1:
You can do this like so:
[DLLImport(@"mydll.dll")]
public static extern void Foo(out ComTypes.IStream Stream, ref uint Size);
Call it like this:
ComTypes.IStream Stream = null;
uint Size;
Foo(out Stream, ref Size);
As normal, make sure your calling conventions match (C# defaults to stdcall, C++ defaults to cdecl).
As an aside, why return the Size separate from the stream since IStream knows its size and will tell you if you ask it to?
来源：https://stackoverflow.com/questions/6361314/pinvoke-and-istream