--==vb6中用图片框任意大小播放AVI电影（New）==--

1. 新建工程，增加一个bas模块
2. 加入一个MCI控件，一个command按钮和一个图片框，设置form的
   ScaleMode property为 Pixels (3).
   
3. .BAS 文件代码:

   
      Type RECT
         Left As Long
         Top As Long
         Right As Long
         Bottom As Long
      End Type
   
      Type MCI_OVLY_RECT_PARMS
         dwCallback As Long
         rc As RECT
      End Type
   
      Global Const MCI_OVLY_WHERE_SOURCE = &H20000
      Global Const MCI_OVLY_WHERE_DESTINATION = &H40000
      Global Const MCI_WHERE = &H843
   
      
      Declare Function mciSendCommand Lib "winmm.dll" _
         Alias "mciSendCommandA" ( _
            ByVal wDeviceID As Long, _
            ByVal uMessage As Long, _
            ByVal dwParam1 As Long,
            dwParam2 As Any) As Long
   
      Declare Function mciGetErrorString Lib "winmm.dll" _
         Alias "mciGetErrorStringA" ( _
            ByVal dwError As Long, _
            ByVal lpstrBuffer As String, _
            ByVal uLength As Long) As Long
    

   
   
   

 Command1_Click()事件:

   Sub Command1_Click ()
      Const MB_OK = 0
      Const MB_ICONSTOP = 16

      Dim Retval&, Buffer$
      Dim dwParam2 As MCI_OVLY_RECT_PARMS

      MMControl1.Command = "Close"
      MMControl1.Filename = "WndSurf1.avi"  '

      
      MMControl1.hWndDisplay = Picture1.hWnd

      MMControl1.Command = "Open"

      '初始化

      dwParam2.dwCallback = MMControl1.hWnd
      dwParam2.rc.Left = 0
      dwParam2.rc.Top = 0
      dwParam2.rc.Right = 0
      dwParam2.rc.Bottom = 0

      '发送消息

            Retval& = mciSendCommand(MMControl1.DeviceID, MCI_WHERE,
                MCI_OVLY_WHERE_SOURCE, dwParam2)

      If Retval& <> 0 Then  '错误发生.
         Buffer$ = Space$(100)
         'Get a description of the error:
         Retval& = mciGetErrorString(Retval&, Buffer$, Len(Buffer$))
         MsgBox Trim$(Buffer$), MB_OK + MB_ICONSTOP, "ERROR"
      Else
         '改变picture box大小:
         Picture1.Width = dwParam2.rc.right - dwParam2.rc.left
         Picture1.Height = dwParam2.rc.bottom - dwParam2.rc.top

         '播放电影

         MMControl1.Wait = True ' Wait for the next command to complete
         MMControl1.Command = "play" 'Play the video clip
         MMControl1.Command = "close"
      End If
   End Sub
 

1. 按f5运行程序