[VBA]求助：怎么选择集中的总数和实际总数对不上呢？？

Sub mm()
On Error Resume Next
    Dim ssetObj As AcadSelectionSet
    Set ssetObj = ThisDrawing.SelectionSets.Add("SSET_OBJ")
    If Err Then
        Err.Clear
        Set ssetObj = ThisDrawing.SelectionSets("SSET_OBJ")
    End If
    On Error GoTo 0
    ' Add objects to a selection set by prompting user to select on the screen
'    ssetObj.Clear
    ssetObj.Clear
    Dim FilterType(0)  As Integer, FilterData(0)  As Variant
    FilterType(0) = 0
    FilterData(0) = "CIRCLE"
    ssetObj.SelectOnScreen FilterType, FilterData
    sngSum = ssetObj.Count
End Sub