Error info of FileSystemObject

[Lane Yu]

I try to use FileSystemObject in VC6 via "#import "scrrun.dll"" IFileSystemPtr spFso(__uuidof(FileSystemObject)); ISupportErrorInfoPtr spSupportE = spFso; HRESULT hrRet = spFso->raw_MoveFolder(_bstr_t(pwszSrc), _bstr_t(pwszDst)); For testing, I assigned pwszSrc and pwszDst with invalid paths. I find that IFileSystem does not support ErrorInfo coz the interface pointer in spSupportE is NULL. The value of hrRet is 0x800a004c, which can not be processed by FormatMessage(). So after MoveFolder() fails, I can't get any error message. However, I used VB to call the same function and got error message "Path not found". How does VB do that? How can I get the same message in VC?

[Steve S]

Well, 800a004c is CTL_E_PATHNOTFOUND (olectl.h), so you probably need to point FormatMessage at the right DLL...

Steve S Developer for hire

[Lane Yu]

I think the common way of using FormatMessage is like this: LPWSTR pwszMsg = NULL; FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM, NULL,hr, 0, (LPWSTR)&pwszMsg, 0, NULL); How can I know which DLL to point and generate correct message? Thanks.

[Steve S]

You could try the one you're #import-ing. You're quite right about that being the most common way, though.

Steve S Developer for hire