Can traverse configuration, but cannot activate the  configuration of (a1,a2,a3,a4)

Private Sub ll1()

  Dim SwModel As ModelDoc2

    Set SwModel = Application.SldWorks.ActiveDoc

  Dim Params As Variant, SwConf As Configuration

    Params = SwModel.GetConfigurationNames

    For ii = 0 To UBound(Params)

       Set SwConf = SwModel.GetConfigurationByName(Params(ii))

       With SwConf

          Debug.Print .Name,

          Debug.Print .BOMPartNoSource,

          Debug.Print .AlternateName,

          .AlternateName = ii

          Debug.Print .Comment,

          .Comment = .Name

          Debug.Print .Type

          ss = .GetParameters(aa, .Name)          

       End With      

    Next ii

End Sub

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In this code

Can traverse Configuration , result is

a2             8            0             a2             0

a3             8            1             a3             0

a4             8            2             a4             0

a1             8            3             a1             0

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Help me

  How to active configuration.

  active configurate a1,a2,a3,a4