VB與Windows資源管理器互拷文件

    通過VB編程來拷貝或移動文件的原理可能大家都十分清楚，可以利用Windows API
SHFileOperation來進行操作，也可以利用VB內置的函數來操作。但是利用這些方法編
寫的程序只能在程序內部執行文件的操作。這里我要向大家介紹如何通過VB編程將程序
中的文件操作同Windows的資源管理器中的拷貝、剪切操作連接起來。
    在Windows的資源管理器中，選中一個或多個文件，在文件上單擊鼠標右鍵，在彈
出菜單中選復制。再切換到另外的目錄，單擊鼠標右鍵，點粘貼。就執行了一次文件的
拷貝操作，那么Windows在拷貝過程中執行了什么操作，是否將整個文件拷貝到剪貼版
上了呢？當然沒有。實際上，windows只是將一個文件結構拷貝到了剪貼版，這個結構
如下：
    tDropFile+文件1文件名+vbNullChar文件2文件名+vbNullChar...+文件N文件名+vbNullChar
其中tDropFile是一個DROPFILES結構，這個結構在Windows API中有定義。在粘貼文件
時，利用API函數 DragQueryFile 就可以獲得拷貝到剪貼版的文件全路徑名，然后就
可以根據獲得的文件名執行文件拷貝函數，實現對文件的粘貼操作。
    下面通過具體的程序來介紹：
    1、在工程文件中加入一個Module，然后在Module中加入如下代碼：
Option Explicit

Private Type POINTAPI
   x As Long
   y As Long
End Type

Private Type SHFILEOPSTRUCT
    hwnd As Long
    wFunc As Long
    pFrom As String
    pTo As String
    fFlags As Integer
    fAnyOperationsAborted As Long
    hNameMappings As Long
    lpszProgressTitle As String
End Type

Private Declare Function SHFileOperation Lib "shell32.dll" Alias _
        "SHFileOperationA" (lpFileOp As SHFILEOPSTRUCT) As Long

'剪貼版處理函數
Private Declare Function EmptyClipboard Lib "user32" () As Long
Private Declare Function OpenClipboard Lib "user32" (ByVal hwnd _
        As Long) As Long
Private Declare Function CloseClipboard Lib "user32" () As Long
Private Declare Function SetClipboardData Lib "user32" (ByVal wFormat _
        As Long, ByVal hMem As Long) As Long
Private Declare Function GetClipboardData Lib "user32" (ByVal wFormat _
        As Long) As Long
Private Declare Function IsClipboardFormatAvailable Lib "user32" _
        (ByVal wFormat As Long) As Long

Private Declare Function DragQueryFile Lib "shell32.dll" Alias _
        "DragQueryFileA" (ByVal hDrop As Long, ByVal UINT As Long, _
        ByVal lpStr As String, ByVal ch As Long) As Long
Private Declare Function DragQueryPoint Lib "shell32.dll" (ByVal _
        hDrop As Long, lpPoint As POINTAPI) As Long
Private Declare Function GlobalAlloc Lib "kernel32" (ByVal wFlags _
        As Long, ByVal dwBytes As Long) As Long
Private Declare Function GlobalFree Lib "kernel32" (ByVal hMem As _
        Long) As Long
Private Declare Function GlobalLock Lib "kernel32" (ByVal hMem As _
        Long) As Long
Private Declare Function GlobalUnlock Lib "kernel32" (ByVal hMem As _
        Long) As Long
Private Declare Sub CopyMem Lib "kernel32" Alias "RtlMoveMemory" _
        (Destination As Any, Source As Any, ByVal Length As Long)

'剪貼版數據格式定義
Private Const CF_TEXT = 1
Private Const CF_BITMAP = 2
Private Const CF_METAFILEPICT = 3
Private Const CF_SYLK = 4
Private Const CF_DIF = 5
Private Const CF_TIFF = 6
Private Const CF_OEMTEXT = 7
Private Const CF_DIB = 8
Private Const CF_PALETTE = 9
Private Const CF_PENDATA = 10
Private Const CF_RIFF = 11
Private Const CF_WAVE = 12
Private Const CF_UNICODETEXT = 13
Private Const CF_ENHMETAFILE = 14
Private Const CF_HDROP = 15
Private Const CF_LOCALE = 16
Private Const CF_MAX = 17

' 內存操作定義
Private Const GMEM_FIXED = &H0
Private Const GMEM_MOVEABLE = &H2
Private Const GMEM_NOCOMPACT = &H10
Private Const GMEM_NODISCARD = &H20
Private Const GMEM_ZEROINIT = &H40
Private Const GMEM_MODIFY = &H80
Private Const GMEM_DISCARDABLE = &H100
Private Const GMEM_NOT_BANKED = &H1000
Private Const GMEM_SHARE = &H2000
Private Const GMEM_DDESHARE = &H2000
Private Const GMEM_NOTIFY = &H4000
Private Const GMEM_LOWER = GMEM_NOT_BANKED
Private Const GMEM_VALID_FLAGS = &H7F72
Private Const GMEM_INVALID_HANDLE = &H8000
Private Const GHND = (GMEM_MOVEABLE Or GMEM_ZEROINIT)
Private Const GPTR = (GMEM_FIXED Or GMEM_ZEROINIT)

Private Const FO_COPY = &H2

Private Type DROPFILES
   pFiles As Long
   pt As POINTAPI
   fNC As Long
   fWide As Long
End Type

Public Function clipCopyFiles(Files() As String) As Boolean
   Dim data As String
   Dim df As DROPFILES
   Dim hGlobal As Long
   Dim lpGlobal As Long
   Dim i As Long
   
   '清除剪貼版中現存的數據
   If OpenClipboard(0&) Then
        Call EmptyClipboard
      
        For i = LBound(Files) To UBound(Files)
            data = data & Files(i) & vbNullChar
        Next i
        data = data & vbNullChar

        '為剪貼版拷貝操作分配相應大小的內存
        hGlobal = GlobalAlloc(GHND, Len(df) + Len(data))
        If hGlobal Then
            lpGlobal = GlobalLock(hGlobal)
         
            df.pFiles = Len(df)
     '將DropFiles結構拷貝到內存中
            Call CopyMem(ByVal lpGlobal, df, Len(df))
     '將文件全路徑名拷貝到分配的內存中。
            Call CopyMem(ByVal (lpGlobal + Len(df)), ByVal data, _
                Len(data))
            Call GlobalUnlock(hGlobal)
         
            '將數據拷貝到剪貼版上
     If SetClipboardData(CF_HDROP, hGlobal) Then
                clipCopyFiles = True
            End If
        End If
        Call CloseClipboard
    End If
End Function

Public Function clipPasteFiles(Files() As String) As Long
   Dim hDrop As Long
   Dim nFiles As Long
   Dim i As Long
   Dim desc As String
   Dim filename As String
   Dim pt As POINTAPI
   Dim tfStr As SHFILEOPSTRUCT
   Const MAX_PATH As Long = 260
   
   '確定剪貼版的數據格式是文件，并打開剪貼版
   If IsClipboardFormatAvailable(CF_HDROP) Then
        If OpenClipboard(0&) Then
            hDrop = GetClipboardData(CF_HDROP)
            '獲得文件數
            nFiles = DragQueryFile(hDrop, -1&, "", 0)
      
            ReDim Files(0 To nFiles - 1) As String
            filename = Space(MAX_PATH)
         
            '確定執行的操作類型為拷貝操作
     tfStr.wFunc = FO_COPY
     '目的路徑設置為File1指定的路徑
            tfStr.pTo = Form1.File1.Path
         
            For i = 0 To nFiles - 1
  '根據獲取的每一個文件執行文件拷貝操作
                Call DragQueryFile(hDrop, i, filename, Len(filename))
                Files(i) = TrimNull(filename)
                tfStr.pFrom = Files(i)
                SHFileOperation tfStr
            Next i
            Form1.File1.Refresh
            Form1.Dir1.Refresh
         
            Call CloseClipboard
        End If
        clipPasteFiles = nFiles
    End If
End Function

Private Function TrimNull(ByVal StrIn As String) As String
   Dim nul As Long
   
   nul = InStr(StrIn, vbNullChar)
   Select Case nul
      Case Is > 1
         TrimNull = Left(StrIn, nul - 1)
      Case 1
         TrimNull = ""
      Case 0
         TrimNull = Trim(StrIn)
   End Select
End Function

    2、在Form1中加入一個FileListBox，Name屬性設置為File1。加入一個DirListBox，
Name屬性設置為Dir1，在Dir1的Change事件中加入如下代碼：
Private Sub Dir1_Change()
   File1.Path = Dir1.Path
End Sub
加入一個DriveListBox，Name屬性設置為Drive1，在Drive1的Change事件中加入如下
代碼：
Private Sub Drive1_Change()
   Dir1.Path = Drive1.Drive
End Sub
加入一個CommandButton，Name屬性設置為cmdCopy，在cmdCopy的Click事件中加入如下
代碼：
Private Sub cmdCopy_Click()
   Dim Files() As String
   Dim Path As String
   Dim i As Long, n As Long
   
   Path = Dir1.Path
   If Right(Path, 1) <> "\" Then
      Path = Path & "\"
   End If
   
   '根據在List1上的選擇建立拷貝文件的列表
   With File1
      For i = 0 To .ListCount - 1
         If .Selected(i) Then
            ReDim Preserve Files(0 To n) As String
            Files(n) = Path & .List(i)
            n = n + 1
         End If
      Next i
   End With
   
   '拷貝文件到Clipboard
   If clipCopyFiles(Files) Then
      MsgBox "拷貝文件成功.", , "Suclearcase/" target="_blank" >ccess"
   Else
      MsgBox "無法拷貝文件...", , "Failure"
   End If
End Sub
加入一個CommandButton，Name屬性設置為cmdPaste，在cmdPaste的Click事件中加入如
下代碼：
Private Sub cmdPaste_Click()
   Dim Files() As String
   Dim nRet As Long
   Dim i As Long
   Dim msg As String
   
   nRet = clipPasteFiles(Files)
   If nRet Then
      For i = 0 To nRet - 1
         msg = msg & Files(i) & vbCrLf
      Next i
      MsgBox msg, , "共粘貼" & nRet & "個文件"
   Else
      MsgBox "從剪貼版粘貼文件錯誤", , "Failure"
   End If
End Sub

    運行文件，在Windows 資源管理器中，選擇文件，再在資源管理器菜單中選 編輯 | 復制
然后在Form1中點擊cmdPaste，從資源管理器中復制的文件就拷貝到Dir1所在的目錄中。從
File1中選擇文件，按cmdCopy復制，再在資源管理器中選 編輯 | 粘貼 ，選擇的文件就被
拷貝到Windows 資源管理器的當前目錄下。
    上面的程序在Windows98 VB6.0下運行通過。

原文轉自：http://www.anti-gravitydesign.com