oracle - 如何处理 appendchunk 和 getchunk 方法？

Question

 Private Function ShowPic()
 Dim bytedata() As Byte
 Dim destfile As Integer
 Dim file As String
 Dim filelen As Long
 Dim numlock As Double
 Dim leftover As Long
 Const blocksize = 100000

 file = App.Path & "\image1.jpeg"

   destfile = FreeFile
   Open file For Binary Access Write As destfile

 filelen = RES(0).ActualSize
        numlock = filelen / blocksize
            leftover = filelen Mod blocksize

   bytedata() = RES(0).GetChunk(leftover)
        Put destfile, , bytedata()
 For i = 1 To numlock
      bytedata() = RES(0).GetChunk(blocksize)
        Put destfile, , bytedata()
 Next i

Close destfile
Picture1.Picture = LoadPicture(App.Path & "\image1.jpeg")
RES.Close
End Function

这是我获取存储在数据库中的图像并显示到图片框中的代码，每当我运行代码错误时，都会发生如下错误：Item cannot found in corresponding ordinal or name