Excel VBA 根据下拉框单元格的值来改变另一个下拉框单元格的值

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
    On Error Resume Next:
    Application.ScreenUpdating = False
    If Target.Column = 7 Then        // 这是需要赋值的DDL列
        If Target.Offset(0, -2).Value = 13 Then  //表示赋值列往前移动两个单位的格子值
            With Selection.Validation
            .Delete
            .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
             xlBetween, Formula1:="No"   //赋值为No
            .IgnoreBlank = True
            .InCellDropdown = True
            .InputTitle = ""
            .ErrorTitle = ""
            .InputMessage = ""
            .ErrorMessage = ""
            .IMEMode = xlIMEModeNoControl
            .ShowInput = True
            .ShowError = True
            End With
        ElseIf Target.Offset(0, -2).Value <> 13 Then
            With Selection.Validation
            .Delete
            .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
             xlBetween, Formula1:="=Exp"  //这里的Exp为自定义名字的列作为数据来源（Formulas -〉Name managers ) 
            .IgnoreBlank = True
            .InCellDropdown = True
            .InputTitle = ""
            .ErrorTitle = ""
            .InputMessage = ""
            .ErrorMessage = ""
            .IMEMode = xlIMEModeNoControl
           .ShowInput = True
            .ShowError = True
            End With
        End If
    ElseIf Target.Column = 8 Then   //下面的逻辑用来控制，当第7列值为No时，会把第8，9，10，11列保护起来不能输入
        If Target.Offset(0, -1).Value = "No" Then
            Target.Locked = True
            Target.Offset(1, -6).Select
        End If
    ElseIf Target.Column = 9 Then
        If Target.Offset(0, -2).Value = "No" Then
            Target.Locked = True
            Target.Offset(1, -7).Select
        End If
    ElseIf Target.Column = 10 Then
        If Target.Offset(0, -3).Value = "No" Then
            Target.Locked = True
            Target.Offset(1, -8).Select
        End If
    ElseIf Target.Column = 11 Then
        If Target.Offset(0, -4).Value = "No" Then
            Target.Locked = True
            Target.Offset(1, -9).Select
        End If
    End If
    Application.ScreenUpdating = True
     
End Sub