browzeforfolder.txt

一部分关于VB编程的小技巧

Public Type BrowseInfo
hwndOwner As Long
pIDLRoot As Long
pszDisplayName As Long
lpszTitle As Long
ulFlags As Long
lpfnCallback As Long
lParam As Long
iImage As Long
End Type

Public Const BIF_RETURNONLYFSDIRS = 1
Public Const MAX_PATH = 260

Public Declare Sub CoTaskMemFree Lib "ole32.dll" (ByVal hMem As Long)
Public Declare Function lstrcat Lib "kernel32" Alias "lstrcatA" (ByVal lpString1 As String, ByVal lpString2 As String) As Long
Public Declare Function SHBrowseForFolder Lib "shell32" (lpbi As BrowseInfo) As Long
Public Declare Function SHGetPathFromIDList Lib "shell32" (ByVal pidList As Long, ByVal lpBuffer As String) As Long


Public Function BrowseForFolder(hwndOwner As Long, sPrompt As String) As String
     
    'declare variables to be used
     Dim iNull As Integer
     Dim lpIDList As Long
     Dim lResult As Long
     Dim sPath As String
     Dim udtBI As BrowseInfo

    'initialise variables
     With udtBI
        .hwndOwner = hwndOwner
        .lpszTitle = lstrcat(sPrompt, "")
        .ulFlags = BIF_RETURNONLYFSDIRS
     End With

    'Call the browse for folder API
     lpIDList = SHBrowseForFolder(udtBI)
     
    'get the resulting string path
     If lpIDList Then
        sPath = String$(MAX_PATH, 0)
        lResult = SHGetPathFromIDList(lpIDList, sPath)
        Call CoTaskMemFree(lpIDList)
        iNull = InStr(sPath, vbNullChar)
        If iNull Then sPath = Left$(sPath, iNull - 1)
     End If

    'If cancel was pressed, sPath = ""
     BrowseForFolder = sPath

End Function