求助：为什么blob字段插入二进制文件，总显示null

Private Sub FileToOLEfield(sFilename As String, OLEField As ADODB.Field)
    Dim FileNumber As Integer
    Dim FileBuffer() As Byte
    Dim FileSize As Long
    Dim ChunkSize As Long     '块大小
    Dim Flag As Integer
    On Error Resume Next
    ChunkSize = 32768
    FileNumber = FreeFile
    Flag = False
   
    Open sFilename For Binary As FileNumber
    FileSize = LOF(FileNumber)
    If FileSize > 0 Then
        Do Until Flag = True
            If (FileSize - Seek(FileNumber)) < ChunkSize Then
                ChunkSize = (FileSize - Seek(FileNumber) + 1)
                Flag = True
            End If
           
            ReDim FileBuffer(ChunkSize) As Byte
           
            Get #FileNumber, , FileBuffer
           
            OLEField.AppendChunk FileBuffer
        Loop
    End If
   
    Close #FileNumber
   
End Sub

Private Sub Command1_Click()
   
  CommonDialog1.DialogTitle = "图片资料"
  CommonDialog1.Filter = "图片文件(*.JPG;*.bmp;*.gif)|*.JPG;*.bmp;*.gif|所有文件(*.*)|*.*"
  CommonDialog1.Action = 1
  Image1.Picture = LoadPicture(CommonDialog1.FileName)

    Dim DcnNWind     As New ADODB.Connection
    Dim rs     As ADODB.Recordset
    Set rs = New ADODB.Recordset
    db_host = "192.168.100.232"
    connstr = "DRIVER={MySQL ODBC 5.1 Driver};SERVER=" + db_host + ";DATABASE=" + "cp" + _
                    ";UID=" + "sp" + ";PWD=" + "" + ";OPTION=3;stmt=SET NAMES GBK"
   DcnNWind.Open connstr
        rs.Open "select * from images ", DcnNWind, adOpenKeyset, adLockPessimistic
       rs.AddNew
            FileToOLEfield CommonDialog1.FileName, rs.Fields("pic")
            rs.Update
            rs.Close
            SaveResourceFile = True
      
End Sub