切换以使代码在Vb.net中更稳定的替代方法

Question

我有一个代码，它是过滤器的一种，显示根据组合框的选定索引显示的元素。我正在使用“选择案例”方法，但似乎该方法不足以应用。

如果autoMBS.tlbCheckBodyCompCtrl_cmb_substrlvl.SelectedIndex=0将什么也不做

如果autoMBS.tlbCheckBodyCompCtrl_cmb_substrlvl.SelectedIndex=1仅显示第1组

如果autoMBS.tlbCheckBodyCompCtrl_cmb_substrlvl.SelectedIndex=2将显示第1组+第2组

如果autoMBS.tlbCheckBodyCompCtrl_cmb_substrlvl.SelectedIndex=3将显示第1组+第2组+第3组

正如您在下面的代码中看到的那样，代码中有很多重复项可以显示出来。

 Public Shared Sub checkGetBodies(ByVal SpckModel As IScrModel, ByVal SpckClass As String)
        Dim Bodies As IScrNamedObjectList
        Bodies = SpckModel.getBodyList(False)
        checkListBodies(Bodies, autoMBS.dgvCheckBodyComp, SpckClass)
        autoMBS.tlbCheckBodyCompCtrl_cmb_filt.Items.Add(SpckClass)
        If autoMBS.tlbCheckBodyCompCtrl_cmb_substr.SelectedIndex = 2 Then
            Dim SubstrsLvL1 As IScrNamedObjectList
            Dim SubstrLvL1 As IScrSubstructure
            Dim nSubstrLvL1 As Integer
            Dim SubstrsLvL2 As IScrNamedObjectList
            Dim SubstrLvL2 As IScrSubstructure
            Dim nSubstrLvL2 As Integer
            Dim SubstrsLvL3 As IScrNamedObjectList
            Dim SubstrLvL3 As IScrSubstructure
            Dim nSubstrLvL3 As Integer

            Select Case autoMBS.tlbCheckBodyCompCtrl_cmb_substrlvl.SelectedIndex
                Case 0
                Case 1
                    SubstrsLvL1 = SpckModel.getSubstrList(False)
                    nSubstrLvL1 = SubstrsLvL1.count
                    If nSubstrLvL1 > 0 Then
                        For x As Integer = 0 To nSubstrLvL1 - 1
                            SubstrLvL1 = SubstrsLvL1.item(x)
                            checkGetSubstrBodies(SubstrLvL1, SubstrLvL1.name)
                        Next
                    End If
                Case 2
                    SubstrsLvL1 = SpckModel.getSubstrList(False)
                    nSubstrLvL1 = SubstrsLvL1.count
                    If nSubstrLvL1 > 0 Then
                        For x As Integer = 0 To nSubstrLvL1 - 1
                            SubstrLvL1 = SubstrsLvL1.item(x)
                            checkGetSubstrBodies(SubstrLvL1, SubstrLvL1.name)

                            SubstrsLvL2 = SubstrLvL1.getSubstrList(False)
                            nSubstrLvL2 = SubstrsLvL2.count
                            If nSubstrLvL2 > 0 Then
                                For y As Integer = 0 To nSubstrLvL2 - 1
                                    SubstrLvL2 = SubstrsLvL2.item(y)
                                    checkGetSubstrBodies(SubstrLvL2, SubstrLvL2.name)
                                Next
                            End If
                        Next
                    End If
                Case 3
                    SubstrsLvL1 = SpckModel.getSubstrList(False)
                    nSubstrLvL1 = SubstrsLvL1.count
                    If nSubstrLvL1 > 0 Then
                        For x As Integer = 0 To nSubstrLvL1 - 1
                            SubstrLvL1 = SubstrsLvL1.item(x)
                            checkGetSubstrBodies(SubstrLvL1, SubstrLvL1.name)

                            SubstrsLvL2 = SubstrLvL1.getSubstrList(False)
                            nSubstrLvL2 = SubstrsLvL2.count
                            If nSubstrLvL2 > 0 Then
                                For y As Integer = 0 To nSubstrLvL2 - 1
                                    SubstrLvL2 = SubstrsLvL2.item(y)
                                    checkGetSubstrBodies(SubstrLvL2, SubstrLvL2.name)

                                    SubstrsLvL3 = SubstrLvL2.getSubstrList(False)
                                    nSubstrLvL3 = SubstrsLvL3.count
                                    If nSubstrLvL3 > 0 Then
                                        For z As Integer = 0 To nSubstrLvL3 - 1
                                            SubstrLvL3 = SubstrsLvL3.item(z)
                                            checkGetSubstrBodies(SubstrLvL3, SubstrLvL3.name)
                                        Next
                                    End If
                                Next
                            End If
                        Next
                    End If
            End Select
        End If

    End Sub