在autocad中如何用VBA修改现有的标注？（特别是如何找到要修改的标注？然后用TextO

Dim ft(0) As Integer
Dim fd(0) As Variant
Dim sset As AcadSelectionSet
If AcadApp.ActiveDocument.SelectionSets.Count = 0 Then
Set sset = AcadApp.ActiveDocument.SelectionSets.Add("ss1")
Else
Set sset = AcadApp.ActiveDocument.SelectionSets.Item(0)
sset.Clear
End If
fd(0) = "DIMENSION"
sset.Select acSelectionSetAll, , , ft, fd
If sset.Count = 0 Then Exit Sub
Dim Ds As AcadDimension    For Each Ds In sset
    If Ds.StyleName = "AA" Then
        Select Case Left(Ds.TextOverride, 3)
            Case "AA"
                Ds.TextOverride = "123456"
........................................