Passing strings from VBA to C++ DLL

Question

I\'m really confused about passing strings from VBA to C++. Here\'s the VBA code:

Private Declare Sub passBSTRVal Lib \"         


        

Answer 1

This is just an illustration to Simon's answer. It shows how to call a native DLL that has parameters of type LPWSTR. As a simple example, I use GetWindowsDirectoryW. As Simon pointed out, always use the "W" version of native DLLs.

Declare PtrSafe Function GetWindowsDirectoryW Lib "kernel32" _ 
   (ByVal lpBuffer As LongPtr, ByVal nSize As Long) As Long

Sub TestGetWindowsDirectoryW()
  Dim WindowsDir As String
  WindowsDir = Space$(256)
  GetWindowsDirectoryW StrPtr(WindowsDir), 256
  MsgBox WindowsDir
End Sub