[vb.net] how to add value to combobox item

Yeah, for most cases, you don't need to create a class with getters and setters. Just create a new Dictionary and bind it to the data source. Here's an example in VB using a for loop to set the DisplayMember and ValueMember of a combo box from a list:

        Dim comboSource As New Dictionary(Of String, String)()
        cboMenu.Items.Clear()
        For I = 0 To SomeList.GetUpperBound(0)
            comboSource.Add(SomeList(I).Prop1, SomeList(I).Prop2)
        Next I
        cboMenu.DataSource = New BindingSource(comboSource, Nothing)
        cboMenu.DisplayMember = "Value"
        cboMenu.ValueMember = "Key"

Then you can set up a data grid view's rows according to the value or whatever you need by calling a method on click:

Private Sub cboMenu_SelectedIndexChanged(sender As Object, e As EventArgs) Handles cboMenu.SelectionChangeCommitted
    SetListGrid(cboManufMenu.SelectedValue)
End Sub