VB.NET Combobox and picture box

Question

If someone can help me I will appreciate it. Thanks in advance, I have a combobox with the values databinding inside a database, I want when I move the records next/previous base on what combobox value is a picturebox display a picture I have stored in my resources.

When I change with mouse combobox value the picture change but when I move between records not. What am I missing there?

  Private Sub TypeComboBox_SelectedIndexChanged(sender As Object, e As EventArgs) Handles TypeComboBox.SelectedIndexChanged

     If TypeComboBox.SelectedItem().ToString() = "1" Then
           PictureBox1.Image = My.Resources.image1
     End if
     If TypeComboBox.SelectedItem().ToString() = "2" Then
             PictureBox1.Image = My.Resources.image2
     End if

      End Sub

Protected Overrides Function ProcessCmdKey(ByRef msg As Message, ByVal keyData As Keys) As Boolean

    'detect left arrow key
    If keyData = Keys.Left Then
        If Me.ToolsBindingSource.Position = 0 Then
            Me.ToolsBindingSource.MoveLast()
            Return True
        Else
            Me.ToolsBindingSource.MovePrevious()
            Return True
        End If
    End If
    'detect right arrow key
    If keyData = Keys.Right Then
        If Me.ToolsBindingSource.Position = Me.ToolsBindingSource.Count - 1 Then
            Me.ToolsBindingSource.MoveFirst()
            Return True
        Else
            Me.ToolsBindingSource.MoveNext()
            Return True
        End If
    End If
    Return MyBase.ProcessCmdKey(msg, keyData)
End Function

Perhaps you should explain EXACTLY what data is contained in your `ComboBox` and EXACTLY how that relates to your images. You ALWAYS need to provide a FULL and CLEAR explanation of the problem. — jmcilhinney, Oct 07 '18 at 14:12
@jmcilhinney sorry i thought that was clear from code, in combobox i have add from vs2017 edit items not by code. I have 1, 2, 3, 4, 5 e.t.c. it suppose that is simple text (string) or i am wrong? Relates to my images not very clear to me, i have in my resources some PNG files with 1,2,3,4,5 and i want when combobox have the string 1 show the PNG file with 1 e.t.c — Endless, Oct 07 '18 at 14:48

jmcilhinney · Accepted Answer · 2018-10-07T22:53:58.020

I would suggest that you create an array containing the Images at the start. You should not repeatedly access the same property of My.Resources because it will create a new object each time. E.g.

Private images As Image() = {My.Resources.image1, My.Resources.image2}

You can then simply use the SelectedIndex of the ComboBox as an index into that array. As long as the two lists are in the same order, the actual values in the ComboBox are irrelevant. E.g.

PictureBox1.Image = images(TypeComboBox.SelectedIndex)

EDIT: Another option would be to create a list that relates the Images and the text, bind that to the ComboBox and then use the SelectedValue, e.g.

Dim imagesAndText = {Tuple.Create("1", My.Resources.image1),
                     Tuple.Create("2", My.Resources.image2)}

With TypeComboBox
    .DisplayMember = "Item1"
    .ValueMember = "Item2"
    .DataSource = imagesAndText
End With

By passing a String and an Image to Tuple.Create, you get a Tuple(Of String, Image). Tuples have properties of the types specified and named Item1, Item2, etc. In this case, Item1 would return the String value and Item2 the Image. After binding, you can access the selected Image via the SelectedValue property, e.g.

PictureBox1.Image = DirectCast(TypeComboBox.SelectedValue, Image)

Thanks a lot, your help make me understood more about coding. It works ok but after so much changes to make it work, i use other approach and at the end i find why didn't work from the start. It was from database i had it at nchar(10), when i change it to nvchar work like a charm. Thanks again — Endless, Oct 07 '18 at 19:21
I have made an edit that it would be worth your while taking a look at. — jmcilhinney, Oct 07 '18 at 22:54
@jimcihinney Thanks a lot, i will keep in mind. I didn't manage to work with all my images and i will keep the 1st option look more tidy. — Endless, Oct 08 '18 at 09:19

VB.NET Combobox and picture box

1 Answers1