Parent/Child ComboBoxes

问题

I have 2 combobox, each having different items but somehow it's a hierarchy of characteristics of the next combobox ie: Combobox1 has VEHICLES, MOTORBIKES and NONE as items. I want to be able to choose Vehicles in combobox1 and Combobox2 updates with items only associated with vehicles ie Sportscar, Sedan etc. The same should happen when I choose Motorcycles in combobox1, it should update combobox2 with items only related to motorcycles.

回答1:

Put this sample code inside the ComboBox1_TextChanged Event for you to have reference.

Private Sub ComboBox1_TextChanged(sender As Object, e As EventArgs) Handles ComboBox1.TextChanged

        ComboBox2.Items.Clear()
        If ComboBox1.Text = "Vehicles" Then
            ComboBox2.Items.Add("Sportscar")
            ComboBox2.Items.Add("Sedan")
        ElseIf ComboBox1.Text = "Motorbikes" Then
            ComboBox2.Items.Add("Harley Davidson")
            ComboBox2.Items.Add("Some motorbikes")
        End If


    End Sub

You can also do this on a Select Case Statement

Private Sub ComboBox1_TextChanged(sender As Object, e As EventArgs) Handles ComboBox1.TextChanged

        ComboBox2.Items.Clear()

        Select Case ComboBox1.Text
            Case "Vehicles"
                ComboBox2.Items.Add("Sportscar")
                ComboBox2.Items.Add("Sedan")
            Case "Motorbikes"
                ComboBox2.Items.Add("Harley Davidson")
                ComboBox2.Items.Add("Some motorbikes")
            Case Else

        End Select


    End Sub

来源：https://stackoverflow.com/questions/65651213/parent-child-comboboxes