我想将选中集合ipFeatSel赋给ipSelSet然后提取出来,为什么不行?

<P> 大家来帮我看一下这段代码</P>
<P> IFeatureSelectionPtr  ipFeatSel(ipFeatLyr);<BR> ipFeatSel->SelectFeatures( ipQF, esriSelectionResultNew, VARIANT_FALSE );</P>
<P><FONT color=#ee1111> ISelectionSetPtr ipSelSet;<BR>ipSelSet = ipFeatSel.SelectionSet;</FONT></P>
<P> CTableView Dlg;<BR> Dlg.SetShowSelection(ipSelSet);<BR> Dlg.DoModal();</P>
<P>我想将选中集合<FONT color=#ee1111>ipFeatSel<FONT color=#000000>赋给</FONT>ipSelSet</FONT><FONT color=#000000>然后提取出来,为什么不行?</FONT></P>