[求助]：多段线选择的问题

jhx1980224

请叫一下各位大侠：如何在cad里只对多段线进行选择。我自己写了一点程序，可是为啥结果老是提示选择的多段线为0，实际上在图形中是有多段线存在的。我把代码附上，请各位大侠给以指点：

Dim ssetobj As AcadSelectionSet
Dim FilterType(0) As Integer
Dim FilterData(0) As Variant

FilterType(0) = 0
FilterData(0) = "lightweightPolyline "

Dim ftype As Variant
Dim fdata As Variant
ftype = FilterType
fdata = FilterData

Set ssetobj = acadapp.ActiveDocument.SelectionSets.Add("i")
ssetobj.Select acSelectionSetAll, , , ftype, fdata
Dim xian As AcadLWPolyline
Dim i As Integer
i = 0
For Each xian In ssetobj
xian.color=acred
i = i + 1
Next
ssetobj.Delete
MsgBox i