CAD 选择集的问题，各位大神帮忙看下。

Option Explicit
Public Sub MTextTotext()
    On Error Resume Next
    Dim ptInsert As Variant
    Dim txtStr As String
    Dim height As Double
    Dim width As Double, bbg As Double
    Dim k As Double, oScale As Double
    Dim pt1, pt2, pt3    
    k = 0.4    
    '确定选择范围区以及表格现有的标高*********************************************
    pt1 = ThisDrawing.Utility.GetPoint(, "框选左上角一个点: ")
    pt2 = ThisDrawing.Utility.GetPoint(, "框选右下角一个点: ")
    pt3 = ThisDrawing.Utility.GetPoint(, "将表格变成7mm高，选取左上角下方邻近点，以确定现有表格高度: ")
    bbg = GetDistance(pt1, pt3)
    Dim SSet As AcadSelectionSet
    oScale = 7 / bbg    
    '选择多行文字*********************************************
    '安全创建选择集
    If Not IsNull(ThisDrawing.SelectionSets.Item("this")) Then
        Set SSet = ThisDrawing.SelectionSets.Item("this")
        SSet.Delete
    End If
    Set SSet = ThisDrawing.SelectionSets.Add("this")
    '定义过滤规则
    Dim filterType(0) As Integer
    Dim filterData(0) As Variant
    filterType(0) = 0
    filterData(0) = "MText"
    SSet.Select acSelectionSetCrossing, pt1, pt2, filterType, filterData
    '创建单行文字***************************************************************
    Dim ptMin As Variant, ptMax As Variant
    Dim objText As AcadText
    Dim objMText As AcadMText
    For Each objMText In SSet
        '获得文字的主要参数
        height = objMText.height
        ptInsert = objMText.InsertionPoint
        ptInsert(1) = ptInsert(1) - height
        txtStr = MtextStringClearFormat(objMText.TextString)
        '文字的限制框宽度
        Set objText = ThisDrawing.ModelSpace.AddText(txtStr, ptInsert, height)
        objText.ScaleFactor = k
        objMText.Delete  '删除原来的多行文字
    Next
    SSet.Delete
     '第二步，在上一步的基础上，实现所有单行文字宽高比，变成K。
      '安全创建选择集
    If Not IsNull(ThisDrawing.SelectionSets.Item("this")) Then
        Set SSet = ThisDrawing.SelectionSets.Item("this")
        SSet.Delete
    End If
    Set SSet = ThisDrawing.SelectionSets.Add("this")
    '定义过滤规则,选持单行文字。
    filterType(0) = 0
    filterData(0) = "Text"
    SSet.Select acSelectionSetCrossing, pt1, pt2, filterType, filterData
    For Each objText In SSet
        objText.ScaleFactor = k
    Next
    SSet.Delete    
    '第三步，表格整体缩放，在现在表格标高的基础上，将单表格高度整体缩放为7mm高，此时文字大概的高度为3.5mm，标准化后以便下一步操作。 
    '安全创建选择集
    Dim objEnt As AcadEntity
    If Not IsNull(ThisDrawing.SelectionSets.Item("this")) Then
        Set SSet = ThisDrawing.SelectionSets.Item("this")
        SSet.Delete
    End If
    Set SSet = ThisDrawing.SelectionSets.Add("this")    
    SSet.Select acSelectionSetCrossing, pt1, pt2
    For Each objEnt In SSet
        objEnt.ScaleEntity pt1, oScale
    Next           
    SSet.Delete
End Sub
Public Function MtextStringClearFormat(MTextString As String) As String '清除掉多行文字中的格式。
    Dim MyString As String
    MyString = MTextString
    MyString = ReplaceByRegExp(MyString, "\\{", Chr(1))
    MyString = ReplaceByRegExp(MyString, "\\}", Chr(2))
    MyString = ReplaceByRegExp(MyString, "\\", Chr(3))
    MyString = ReplaceByRegExp(MyString, "\\S([^;]*?)(\^|#)([^;]*?);", "$1$3")
    MyString = ReplaceByRegExp(MyString, "\\S([^;]*?);", "$1")
    MyString = ReplaceByRegExp(MyString, "(\\P|\\O|\\o|\\L|\\l|\{|\})", "")
    MyString = ReplaceByRegExp(MyString, "\\[^;]*?;", "")
    MyString = ReplaceByRegExp(MyString, "\x01", "{")
    MyString = ReplaceByRegExp(MyString, "\x02", "}")
    MyString = ReplaceByRegExp(MyString, "\x03", "")
   MtextStringClearFormat = Trim(MyString)
End Function
Public Function ReplaceByRegExp(ByVal Mystrig As String, ByVal TxtFind As String, ByVal TxtReplace As String)
     Dim RE As Object
     Set RE = ThisDrawing.Application.GetInterfaceObject("Vbscript.RegExp")    
    RE.IgnoreCase = False
     RE.Global = True    
     RE.Pattern = TxtFind
    ReplaceByRegExp = RE.Replace(Mystrig, TxtReplace)
     Set RE = Nothing
 End Function
'计算两点之间距离
Public Function GetDistance(sp As Variant, ep As Variant) As Double
    Dim x As Double
    Dim y As Double
    Dim z As Double    
    x = sp(0) - ep(0)
    y = sp(1) - ep(1)
    z = sp(2) - ep(2)    
    GetDistance = Sqr((Sqr((x ^ 2) + (y ^ 2)) ^ 2) + (z ^ 2))
End Function