关于在图层画线的程序出错，请大家帮我看看这段程序有什么问题

<P ><FONT face="Times New Roman">CMapXLayer layer = m_ctrlMapX.GetLayers().Item("huhu");</FONT></P>
<P ><FONT face="Times New Roman">               CMapXFeature obj,newobj;</FONT></P>
<P ><FONT face="Times New Roman">              CMapXPoints pts;</FONT></P>
<P ><FONT face="Times New Roman">    CMapXPoint p,pt;</FONT></P>
<P ><FONT face="Times New Roman">       CMapXStyle style;</FONT></P>
<P ><FONT face="Times New Roman">     style.CreateDispatch (style.GetClsid ());</FONT></P>
<P ><FONT face="Times New Roman">     style.PickLine();</FONT></P>
<P ><FONT face="Times New Roman">        newobj.CreateDispatch(newobj.GetClsid());</FONT></P>
<P ><FONT face="Times New Roman">                      newobj.Attach(m_ctrlMapX.GetDispatch());</FONT></P>
<P ><FONT face="Times New Roman">        newobj.SetType(miFeatureTypeLine);</FONT></P>
<P ><FONT face="Times New Roman">      newobj.SetStyle(m_ctrlMapX.GetDefaultStyle());</FONT></P>
<P ><FONT face="Times New Roman">         pt.CreateDispatch (pt.GetClsid ());</FONT></P>
<P ><FONT face="Times New Roman">pts.CreateDispatch (pts.GetClsid ());</FONT></P>
<P ><FONT face="Times New Roman">    pt.Set(m_ctrlMapX.GetCenterX()+10.0,m_ctrlMapX.GetCenterY());</FONT></P>
<P ><FONT face="Times New Roman">   pts.Add(pt);</FONT></P>
<P ><FONT face="Times New Roman">    pt.Set(m_ctrlMapX.GetCenterX()+11.0,m_ctrlMapX.GetCenterY() + 4.0);</FONT></P>
<P ><FONT face="Times New Roman">    pts.Add(pt);</FONT></P>
<P ><FONT face="Times New Roman">    pt.Set(m_ctrlMapX.GetCenterX()+9.0,m_ctrlMapX.GetCenterY()-11.0);</FONT></P>
<P ><FONT face="Times New Roman">    pts.Add(pt);</FONT></P>
<P ><FONT face="Times New Roman">       newobj.GetParts().Add(pts);</FONT></P>
<P ><FONT face="Times New Roman">   layer.AddFeature(newobj); </FONT></P>
<P ><FONT face="Times New Roman">我用这段程序在huhu这个图层上添加一些线条，程序运行没有出错，但就是加不进去，请大家帮我看看哪里出问题了，是不是还缺少什么</FONT></P>
<P ><FONT face="Times New Roman">  </FONT></P>