果然可以
Dim stId As ObjectId = HostApplicationServices.WorkingDatabase.TextStyleTableId
Dim stObj As TextStyleTable = stId.GetObject(OpenMode.ForRead)
For Each trId As ObjectId In stObj
Dim tr As TextStyleTableRecord = trId.GetObject(OpenMode.ForRead)
If tr.Name = "USER3" Then
mtxtTitle.TextStyleId = tr.ObjectId
End If
Next