Question Image from DB issues

[gchq]

Hi there

A DB Table is brought into a DataTable.

If the value of the long binary field in null it should return a default image, but that is not happening

Here is the PictureBox control

Dim Default_LogoPic As New PictureBox
            With Default_LogoPic
                .Size = New Point(70, 70)
                .Location = New Point(320, 60)
                If Form1.AnnualData.Columns.Contains("Logo_Flag") Then
                    Dim vImage() As Byte = NullImage(Row("Logo_Image"))
                    Dim vStream As New MemoryStream(vImage)
                    .Image = Image.FromStream(vStream)
                End If
            End With
            StationaryTab.Controls.Add(Default_LogoCB)

.. and here is the null value function

Public Function NullImage(ByVal obj As Object) As Byte()
        Dim Img As Image = My.Resources.Cross
        Dim imgStream As MemoryStream = New MemoryStream()
        Img.Save(imgStream, System.Drawing.Imaging.ImageFormat.Png)
        imgStream.Close()
        Dim byteArray As Byte() = imgStream.ToArray()
        imgStream.Dispose()
        If Not obj.Equals(DBNull.Value) Then
            Dim Str As String = Convert.ToString(obj)
            Dim encoding As New System.Text.ASCIIEncoding()
            byteArray = encoding.GetBytes(Str)
        End If
        Return byteArray
    End Function

So far only got round to testing with nullvalues - no errors, but no default image loading either! Any ideas?

Thanks

 

[jmcilhinney]

Surely the very first thing you should be doing is checking for NULL. If the field is NULL then you simply get the default Image; no need for any MemoryStream at all.

If row.IsNull("Logo_Image") Then
    .Image = My.Resources.Cross
Else
    Dim data As Byte() = DirectCast(row("Logo_Image"), Byte())

    'Get Image via MemoryStream.
End

 

[gchq]

jmcilhinney - thanks for your reply.

The idea was took keep the default image in one function - and it would appear it DOES work! I managed to load the same control name twice instead of the one I needed

Dim Default_LogoPic As New PictureBox

StationaryTab.Controls.Add(Default_LogoCB)

Thank you again for taking the time to reply!