ExtensionLineDirection and  DimensionLineDirection

What is the difference between the ExtensionLineDirection statement and DimensionLineDirection statement.

code is

'

Private Sub del1()

    Dim swApp As SldWorks.SldWorks, swModel As ModelDoc2

        Set swApp = Application.SldWorks

        Set swModel = swApp.ActiveDoc

    Dim SwSelMgr As SelectionMgr

        Set SwSelMgr = swModel.SelectionManager

    Dim swDispDim As DisplayDimension, swDim As Dimension

        Set swDispDim = SwSelMgr.GetSelectedObject5(1)

        With swDispDim

             Debug.Print .Type2

             Set swDim = .GetDimension

        End With

    Dim vDir, vDir1, Str

    Dim MathVect  As MathVector, MathVect2 As MathVector

        With swDim

            Set MathVect = .DimensionLineDirection

            vDir = MathVect.ArrayData

            Str = "DimensionLineDirection is Direction ("

            For ii = 0 To 2

                 Str = Str & vDir(ii) & ","

            Next ii

            Str = Left(Str, Len(Str) - 1) & ")"

            Debug.Print Str

            Set MathVect = .ExtensionLineDirection

            vDir1 = MathVect.ArrayData

            Str = "ExtensionLineDirection is Direction ("

            For ii = 0 To 2

                 Str = Str & vDir1(ii) & ","

            Next ii

            Str = Left(Str, Len(Str) - 1) & ")"

            Debug.Print Str

            Stop

            Stop

        End With

        Stop

End Sub

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2017 SOLIDWORKS API Help - ExtensionLineDirection Property (IDimension)  http://help.solidworks.com/2017/english/api/sldworksapi/solidworks.interop.sldworks~solidworks.interop.sldworks.idimension~extensionlinedirection.html

2017 SOLIDWORKS API Help - DimensionLineDirection Property (IDimension)  http://help.solidworks.com/2017/english/api/sldworksapi/solidworks.interop.sldworks~solidworks.interop.sldworks.idimension~dimensionlinedirection.html

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