Vb6中如何使用SHGetKnownFolderPath函数

Question

我目前正在将Windows 7支持添加到现有的Vb6项目中，并且我遇到了使用SHGetFolderPath定位特殊文件夹路径的问题，这在Vista开始的Windows版本上不支持。我知道我应该使用SHGetKnownFolderPath，但我找不到一个很好的例子，在VB6中实现使用SHGetKnownFolderPath API调用。

Answer 1

更容易使用Shell对象建议延迟绑定，因为Microsoft没有仔细考虑与此对象的兼容性。

Const ssfCOMMONAPPDATA = &H23 
Const ssfLOCALAPPDATA = &H1c
Const ssfAPPDATA = &H1a
Dim strAppData As String 
strAppData = _ 
    CreateObject("Shell.Application").NameSpace(ssfAPPDATA).Self.Path 

Answer 2

从shfolder.dll使用SHGetFolderPath在Vista和Win7下工作良好:

Private Declare Function SHGetFolderPath Lib "shfolder" Alias "SHGetFolderPathA" (ByVal hWnd As Long, ByVal csidl As Long, ByVal hToken As Long, ByVal dwFlags As Long, ByVal szPath As String) As Long

然后在这些CSIDL_Xxx常量上声明一个enum:

Public Function GetSpecialFolder(ByVal eType As MySpecialFolderType) As String
    GetSpecialFolder = String(1000, 0)
    Call SHGetFolderPath(0, eType, 0, 0, GetSpecialFolder)
    GetSpecialFolder = Left$(GetSpecialFolder, InStr(GetSpecialFolder, Chr$(0)) - 1)
End Function

Answer 3

使用以下代码本文vba/vb6在模块WINAPI32.bas的顶部声明API调用

Private Declare Function SHGetSpecialFolderLocation Lib "shell32.dll" _
                    (ByVal hwndOwner As Long, ByVal nFolder As Long, _
                     pidl As ITEMIDLIST) As Long
Private Declare Function SHGetPathFromIDList Lib "shell32.dll" Alias "SHGetPathFromIDListA" _
                        (ByVal pidl As Long, ByVal pszPath As String) As Long
Private Type SHITEMID
    cb As Long
    abID As Byte
End Type
Private Type ITEMIDLIST
    mkid As SHITEMID
End Type

新增公共函数:

Public Function SHGetSpecialFolderLocationVB(ByVal lFolder As Long) As String
    Dim lRet As Long, IDL As ITEMIDLIST, sPath As String
    lRet = SHGetSpecialFolderLocation(100&, lFolder, IDL)
    If lRet = 0 Then
        sPath = String$(512, chr$(0))
        lRet = SHGetPathFromIDList(ByVal IDL.mkid.cb, ByVal sPath)
        SHGetSpecialFolderLocationVB = Left$(sPath, InStr(sPath, chr$(0)) - 1)
    Else
        SHGetSpecialFolderLocationVB = vbNullString
    End If
End Function

添加了一个新功能来检查Windows版本Vista或更高版本

Public Function IsVistaOrHigher() As Boolean
    Dim osinfo As OSVERSIONINFO
    Dim retvalue As Integer
    Dim bVista As Boolean
    bVista = False
    osinfo.dwOSVersionInfoSize = 148
    osinfo.szCSDVersion = Space$(128)
    retvalue = GetVersionExA(osinfo)
    If osinfo.dwPlatformId = 2 Then
        If osinfo.dwMajorVersion >= 6 Then
            bVista = True
        End If
    End If
    IsVistaOrHigher = bVista
End Function

修改了之前调用SHGetFolderPath的方法

Public Function SHGetFolderPathVB(ByVal lFolder As Long) As String
    Dim path As String
    If IsVistaOrHigher() Then
        SHGetFolderPathVB = SHGetSpecialFolderLocationVB(lFolder)
    Else
        path = Space$(MAX_PATH)
        SHGetFolderPath 0, lFolder, 0, SHGFP_TYPE_CURRENT, path
        SHGetFolderPathVB = Left(path, InStr(path, vbNullChar) - 1)
    End If
End Function

作品太棒了!

Answer 4

一个迟来的回答。但它实际上展示了如何在x64 VBA中使用SHGetKnownFolderPath，并且没有解决方法来避免它。

我使用了这个德语来源:https://dbwiki.net/wiki/VBA_Tipp:_Spezielle_Verzeichnisse_ermitteln

给出的解决方案不适用于x64 Office。所以我改了名字。从VBA调用本机DLL需要

• 新关键字PtrSafe的使用情况。
• 所有指针使用LongPtr而不是Long。
• 通过StrPtr函数将VBA字符串转换为LongPtr对象。
• 调用Unicode版本的DLL，通常用"w"标记

代码:

Public Const FOLDERID_ProgramFiles1  As String = "{905E63B6-C1BF-494E-B29C-65B732D3D21A}"
Public Type GUID
 Data1 As Long
 Data2 As Integer
 Data3 As Integer
 Data4(7) As Byte
End Type
Public Const S_OK As Long = 0
Public Const WIN32_NULL As Long = 0
Public Declare PtrSafe Sub CoTaskMemFree Lib "ole32" (ByVal hMem As LongPtr)
Public Declare PtrSafe Function CLSIDFromString Lib "ole32" ( _
  ByVal lpszGuid As LongPtr, _
  ByRef pGuid As GUID) As Long
Public Declare PtrSafe Function lstrlenW Lib "kernel32" ( _
 ByVal lpString As LongPtr) As Long
Public Declare PtrSafe Function SHGetKnownFolderPath Lib "shell32" ( _
  ByRef rfid As GUID, _
  ByVal dwFlags As Long, _
  ByVal hToken As Long, _
  ByRef pszPath As LongPtr) As Long
Public Declare PtrSafe Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" ( _
 ByVal Destination As LongPtr, _
 ByVal Source As LongPtr, _
 ByVal length As Long)
Public Function GetBstrFromWideStringPtr(ByVal lpwString As LongPtr) As String
  Dim length As Long
  If (lpwString) Then length = lstrlenW(lpwString)
  If (length) Then
    GetBstrFromWideStringPtr = Space$(length)
    CopyMemory StrPtr(GetBstrFromWideStringPtr), lpwString, length * 2
  End If
End Function
Public Function GetKnownFolder(ByVal KnownFolderID As String) As String
'Returns empty String on any error.
  Dim ref As GUID
  Dim pszPath As LongPtr
  If (CLSIDFromString(StrPtr(KnownFolderID), ref) = S_OK) Then
    If (SHGetKnownFolderPath(ref, 0, WIN32_NULL, pszPath) = S_OK) Then
      GetKnownFolder = GetBstrFromWideStringPtr(pszPath)
      CoTaskMemFree pszPath
    End If
  End If
End Function
Sub TestKnownFolder()
 MsgBox GetKnownFolder(FOLDERID_ProgramFiles1)
End Sub

在上面的链接中，您可以找到所有FOLDERID_Blah字符串。