Help! 怎样将CAD的DWG格式文件加入MO

<P>以下是我加入的代码，但运行不了，不清楚哪里有错误。运行后的错误提示为
实时错误‘91’
对象变量或With块变量未设置</P>
<P>Option Explicit                          
Dim dc As MapObjects2.DataConnection
Private Sub Command1_Click()
Dim lyr As New MapObjects2.MapLayer
dc.Database = "[CADArea]C:\CAD"
Set lyr.GeoDataset = dc.FindGeoDataset("Drawing1.dwg")
If lyr.Valid Then
lyr.Symbol.Color = moRed
lyr.Symbol.Size = 3
lyr.Symbol.SymbolType = moLineSymbol
Map1.Refresh
Map1.Layers.Add lyr
Else
MsgBox "null"
Exit Sub
End If
End Sub</P>
<P>Private Sub Map1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
If Button = 1 Then
Map1.Extent = Map1.TrackRectangle
Else
Map1.Pan
End If
End Sub</P>
<P>Private Sub Form1_Load()
Command1.Caption = "显示CAD文件"
End Sub</P>
<P>我刚接触MO没多久，各位大哥大姐帮忙看看，谢过啦。
</P>

mo view的例子可以打开的 啊

<P>哦，已经解决啦，谢谢<img src="http://www.gisempire.com/bbs/Skins/Default/emot/em12.gif"><img src="http://www.gisempire.com/bbs/Skins/Default/emot/em12.gif"></P>