Wrapping MS P2P sdk

Hey all, I'm writing a wrapper for XP's peer2peer sdk so that it can run under managed code, and I can use it as a library in some apps I'm working on. I'm not a huge C guru (which is what the SDK is written in) but I have some decent knowledge of C++, which is what I'm writing the wrapper in. I have a question, I'm abstracting the SDK to a much higher level, and I am wondering how I can convert a System::String (managed string in c++) to a PWSTR, the "string" class that they are using in the SDK. I just can't figure it out other than some realy brute force methods....is there a function that will help me convert these things Any thoughts/ideas would be greatly appreciated!

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Wrapping MS P2P sdk

Monarghel
Hmmm, I think I may have found it out...do you think this will cause problems It complies at least :)

String *peer = something that we get passed

wchar_t peerChar = peer->get_Chars(peer->Length);

PWSTR pwzFriendlyName = &peerChar;
zobrakster
For const whar_t* parameters you can use the PtrToStringChars
utility function in vcclr.h. For non-const parameters you'll have to create a copy of the string, since managed strings are immutable.
Kiran Suthar
Tried that...here's my code....

PWSTR pwzFriendlyName = PtrToStringChars(peer);

where peer is of type System::String

The error I'm now getting is:
error C2440: 'initializing' : cannot convert from 'const __wchar_t __gc *' to 'PWSTR'

I see that __gc is what it's returning so it's garbage collected.....I think that may cause a problem to start with...but I still can't figure out how to get my desired PWSTR.
RatOmeter
Got it all figured out....

IntPtr tmp= Marshal::StringToCoTaskMemUni(peer);

PWSTR fName = (PWSTR)tmp.ToPointer();

I belive this code does the same as the above posted code does....
shy_man
You must first assign the return value to a pinning pointer:

const wchar_t __pin *tmp = PtrToStringChars(peer);
PWSTR pwzFriendlyName = (PWSTR)tmp;

The other code you posted doesn't do what you want.
Wrapping MS P2P sdk

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