[求教]vc+mo问题求教

<P>新建一个空的图层,代码如下:</P>
<P> CMoRecordset sourceSet;<br> sourceSet = roadLayer.GetRecords();<br> CMoFields sourceFields( sourceSet.GetFields() );<br> CMoField sourceField( sourceFields.Item( COleVariant(TEXT("shape"))) );</P>
<P> // Create data set and table to descript<br> CMoDataConnection con;<br> if( !con.CreateDispatch(TEXT("MapObjects2.DataConnection")) )<br>  return;<br> CMoGeoDataset desDataSet;</P>
<P> CMoTableDesc desTableDesc;<br> if( !desTableDesc.CreateDispatch( TEXT("MapObjects2.TableDesc") ) )<br>  return;<br> desTableDesc.SetFieldCount( 4 );<br> desTableDesc.SetFieldName( 0, "CODE");<br> desTableDesc.SetFieldType( 0, moString);<br> desTableDesc.SetFieldLength( 0, 10);<br> desTableDesc.SetFieldName( 1, "BM");<br> desTableDesc.SetFieldType( 1, moLong);<br> desTableDesc.SetFieldName( 2, "NAME");<br> desTableDesc.SetFieldType( 2, moString);<br> desTableDesc.SetFieldLength( 2, 14);<br> desTableDesc.SetFieldName( 3, "LENGTH");<br> desTableDesc.SetFieldType( 3, moDouble);</P>
<P> desDataSet = con.AddGeoDataset( "road", moShapeTypeLine, desTableDesc, COleVariant(short(0)), COleVariant(short(0)));<br> if( LPDISPATCH(desDataSet) )<br>  return;<br> CMoMapLayer newLayer;<br> if( !newLayer.CreateDispatch(TEXT("MapObjects2.MapLayer")) )<br>  return;<br> newLayer.SetName( "road" );<br> newLayer.SetGeoDataset( desDataSet );</P>
<P>但是在最后一句newLayer.SetGeoDataset( desDataSet );时,总是给我报异常~~~实在不知道为什么?还请指教,谢谢~~</P>

<FONT color=#ff0000>帝国出品，必属精品</FONT>

<P>CMoGeoDataset moDst(m_curConnection.AddGeoDataset(lyrName+"_temp",moPoint,tblDsc,va,va));<BR>//add to project<BR>if(LPDISPATCH(moDst)==NULL)<BR>  return FALSE;<BR>//加点<BR>CMoMapLayer newLayer;<BR>if(!newLayer.CreateDispatch("MapObjects2.MapLayer"))<BR>{<BR>  throw "init maplayer Wrong!";<BR>  return FALSE;<BR>}</P>
<P>newLayer.SetGeoDataset(moDst);</P>
<P>试一下上面的写法。我怀疑你的desDataSet 创建有问题。</P>

<P><BR>newLayer.SetGeoDataset(moDst);<BR></P>