ขอโค้ด VB.Net 2010 + SqlServer เลือกจังหวัด อำเภอ ตำบล รหัสไปรษณีย์

Private Sub Call_province()

        Try




            Dim sqlprovince As String = ""
            sqlprovince = "SELECT * FROM province"
            sqlprovince &= " ORDER BY PROVINCEID"
            da = New SqlDataAdapter(sqlprovince, Conn)
            da.Fill(ds, "province")

            If ds.Tables("province").Rows.Count <> 0 Then
                With cboPROVINCE_TH
                    .DataSource = ds.Tables("province")
                    .DisplayMember = "PROVINCE_TH"
                    .ValueMember = "PROVINCEID"
                    .DataBindings.Clear()
                    .DataBindings.Add("SelectedValue", ds, "organization.PROVINCEID")
                End With
            End If
        Catch ex As Exception
            cboPROVINCE_TH.Text = Nothing
        End Try

    End Sub

    Private Sub call_amphur()
        ds.Tables.Clear()
        Try
            Dim sqldistrict As String = ""
            sqldistrict = "SELECT *  FROM district"
            If cboPROVINCE_TH.ValueMember = "" Then
                Exit Sub
            Else
                sqldistrict &= " where PROVINCEID = '" & CStr(cboPROVINCE_TH.SelectedValue) & "'"

                sqldistrict &= " ORDER BY DISTRICTID"
                da = New SqlDataAdapter(sqldistrict, Conn)
                da.Fill(ds, "district")
                If ds.Tables("district").Rows.Count <> 0 Then
                    With cboDISTRICT_TH
                        .DataSource = ds.Tables("district")
                        .DisplayMember = "DISTRICT_TH"
                        .ValueMember = "DISTRICTID"
                        .DataBindings.Clear()
                        .DataBindings.Add("SelectedValue", ds, "organization.DISTRICTID")
                    End With
                End If
            End If

        Catch ex As Exception

            cboDISTRICT_TH.Text = Nothing
        End Try



    End Sub

    Private Sub call_tambon()
        ds.Tables.Clear()
        Try
            Dim sqltambon As String = ""
            sqltambon = "SELECT *  FROM tambon"
            If cboDISTRICT_TH.ValueMember = "" Then
                Exit Sub
            Else
                sqltambon &= " where DISTRICTID = '" & CStr(cboDISTRICT_TH.SelectedValue) & "'"

                sqltambon &= " ORDER BY TAMBONID"
                da = New SqlDataAdapter(sqltambon, Conn)
                da.Fill(ds, "tambon")
                If ds.Tables("tambon").Rows.Count <> 0 Then
                    With cboTAMBON_TH
                        .DataSource = ds.Tables("tambon")
                        .DisplayMember = "TAMBON_TH"
                        .ValueMember = "TAMBONID"


                        .DataBindings.Clear()




                        .DataBindings.Add("SelectedValue", ds, "organization.TAMBONID")
                    End With
                End If
            End If



        Catch ex As Exception

            cboTAMBON_TH.Text = Nothing
        End Try





    End Sub





    Private Sub cboPROVINCE_TH_SelectedValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboPROVINCE_TH.SelectedValueChanged
        call_amphur()
    End Sub

    Private Sub cboDISTRICT_TH_SelectedValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboDISTRICT_TH.SelectedValueChanged
        call_tambon()
    End Sub