从Microsoft Access数据库

Question

这是我保存和检索的代码，检索无效。

Private Sub btnsave_Click(sender As Object, e As EventArgs) Handles btnsave.Click
    Dim str As New MemoryStream
    Pic.Image.Save(str, Imaging.ImageFormat.Jpeg)
    Dim buffer(CInt(str.Length - 1)) As Byte
    str.Position = 0
    str.Read(buffer, 0, CInt(str.Length))
    Try
        Dim d As New DAL
        If printchck.Checked = True Then
            d.Dataedit(String.Format("insert into labdetails ( labnme,labspecial,labadress,labphone,labtime,lablogo,labprint)values('{0}','{1}','{2}','{3}','{4}','{5}',{6})", txtlabname.Text, txtspeciality.Text, txtadress.Text, txtphone.Text, txttime.Text, buffer, "Yes"))
        Else
            d.Dataedit(String.Format("insert into labdetails ( labnme,labspecial,labadress,labphone,labtime,lablogo,labprint)values('{0}','{1}','{2}','{3}','{4}','{5}',{6})", txtlabname.Text, txtspeciality.Text, txtadress.Text, txtphone.Text, txttime.Text, buffer, "No"))

        End If
        MessageBox.Show("تم الحفظ")  ' saved
    Catch ex As Exception
        MessageBox.Show(ex.Message)
    End Try
End Sub

Sub retriveimage()
    Dim dt As DataTable = New DAL().selectdatatable("select lablogo from labdetails")

    Dim img_buffer() As Byte = dt.Rows(0).Item("lablogo")

    Dim img_stream As New MemoryStream(img_buffer)
    img_stream.Write(img_buffer, 0, img_buffer.Length)
    '  Pic.Image = Image.FromStream(img_stream)


    Pic.Image = Image.FromStream(img_stream)  ' error here, Parameter is not valid
    Pic.SizeMode = PictureBoxSizeMode.StretchImage
    img_stream.Close()
End Sub