Imports Gizmox.WebGUI.Forms

Public Class TwoComboboxes

    Dim ValueTable As DataTable

    Dim ValueView As DataView

    Dim CountryTable As DataTable

    Friend WithEvents cboCountry As Gizmox.WebGUI.Forms.ComboBox

    Friend WithEvents cboCity As Gizmox.WebGUI.Forms.ComboBox

    Sub New()

        ' This call is required by the Windows Form Designer.

        InitializeComponent()

        ' Add any initialization after the InitializeComponent() call.

        CreateComboboxes()

    End Sub

    Private Sub TwoComboboxes_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        ValueTable = New DataTable

        ValueTable.Columns.Add("Country", GetType(String))

        ValueTable.Columns.Add("City", GetType(String))

        CountryTable = New DataTable

        CountryTable.Columns.Add("Country")

        PopulateTables()

        cboCity.DataSource = ValueView

        cboCity.ValueMember = "City"

        cboCity.DisplayMember = "City"

        cboCountry.DataSource = CountryTable

        cboCountry.DisplayMember = "Country"

        cboCountry.ValueMember = "Country"

    End Sub

    Private Sub CreateComboboxes()

        '

        'cboCountry

        '

        Me.cboCountry.Location = New System.Drawing.Point(12, 38)

        Me.cboCountry.Name = "cboCountry"

        Me.cboCountry.Size = New System.Drawing.Size(251, 21)

        Me.cboCountry.TabIndex = 0

        Me.cboCountry.Text = "ComboBox1"

        '

        'cboCity

        '

        Me.cboCity.Location = New System.Drawing.Point(312, 38)

        Me.cboCity.Name = "cboCity"

        Me.cboCity.Size = New System.Drawing.Size(307, 21)

        Me.cboCity.TabIndex = 1

        Me.cboCity.Text = "ComboBox2"

        Me.Controls.Add(Me.cboCity)

        Me.Controls.Add(Me.cboCountry)

    End Sub

    Private Sub PopulateTables()

        CountryTable.Rows.Add("Iceland")

        CountryTable.Rows.Add("UK")

        CountryTable.Rows.Add("Israel")

        ValueTable.Rows.Add("Iceland", "Reykjavik")

        ValueTable.Rows.Add("Iceland", "Akureyri")

        ValueTable.Rows.Add("Iceland", "Husavik")

        ValueTable.Rows.Add("Iceland", "Kopasker")

        ValueTable.Rows.Add("UK", "London")

        ValueTable.Rows.Add("UK", "Birmingham")

        ValueTable.Rows.Add("UK", "Manchester")

        ValueTable.Rows.Add("Israel", "Kfar Saba")

        ValueTable.Rows.Add("Israel", "Tel Aviv")

        ValueTable.Rows.Add("Israel", "Jerusalem")

        ValueView = New DataView(ValueTable)

    End Sub

    Private Sub cboCountry_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboCountry.SelectedIndexChanged

        If cboCountry.SelectedItem Is Nothing Then

            ValueView.RowFilter = "1 = 0"

        Else

            Dim dr As DataRow = cboCountry.SelectedItem.Row()

            ValueView.RowFilter = "Country = '" + dr("Country") + "'"

            cboCity.Update()

        End If

    End Sub

End Class