VB Forum / Win API / September 2003

I'm having a problem getting the size of a file.
For a "small" file it all works fine.However for a file of over 2gb it gives
a strange result.

WFD.nFileSizeLow becomes -1347188508

And the file itself has a size of 2,947,778,788

Any ideas what I'm doing wrong?

Below the code I'm using.

Private Declare Function FindFirstFile Lib "kernel32" Alias "FindFirstFileA"
_
                                         (ByVal lpFileName As String, _
                                          ByRef lpFindFileData As
WIN32_FIND_DATA) As Long

Private Const MAX_PATH As Long = 260
Private Const INVALID_HANDLE_VALUE = -1
Private Const MAXDWORD As Long = &HFFFF

Private Type FILETIME
  dwLowDateTime As Long
  dwHighDateTime As Long
End Type

Private Type WIN32_FIND_DATA
  dwFileAttributes As Long
  ftCreationTime As FILETIME
  ftLastAccessTime As FILETIME
  ftLastWriteTime As FILETIME
  nFileSizeHigh As Long
  nFileSizeLow As Long
  dwReserved0 As Long
  dwReserved1 As Long
  cFileName As String * MAX_PATH
  cAlternate As String * 14
End Type

Function GetFileSize(ByVal filePath As String) as double
   Dim WFD As WIN32_FIND_DATA
   Dim hFile As Long
   Dim hTotalSize As Long
   Dim tGetFileSize As Double
   hFile = FindFirstFile(filePath, WFD)
   If hFile <> INVALID_HANDLE_VALUE Then
       tGetFileSize = (WFD.nFileSizeHigh * (maxword + 1)) +
WFD.nFileSizeLow
   Else
       tGetFileSize = -1
   End If
   GetFileSize = tGetFileSize
End Function