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c# mapx 从读取数据在图层中显示的有关问题

热度:430   发布时间:2016-05-05 06:40:25.0
c# mapx 从读取数据在图层中显示的问题
在网上结合http://bbs.cnw.com.cn/thread-185210-1-1.html做的。
我的代码如下:
 private void CreatNewLayerfromDB(string layerName, ADODB.Recordset rsNoPass)
  { 
  DeleteLayerByName(layerName); //将原有层删除 
  CMapXFields flds = new FieldsClass();
  // Describe the structure of the Unbound dataset 
  flds.Add("ID", "ID", AggregationFunctionConstants.miAggregationIndividual,FieldTypeConstants.miTypeNumeric);
  flds.Add("layer", "layer", AggregationFunctionConstants.miAggregationIndividual, FieldTypeConstants.miTypeString);
  flds.Add("point_x", "point_x", AggregationFunctionConstants.miAggregationSum,FieldTypeConstants.miTypeNumeric);  //经度 
  flds.Add("point_y", "point_y", AggregationFunctionConstants.miAggregationSum,FieldTypeConstants.miTypeNumeric);  //纬度 
   
  CMapXBindLayer bindLayerObject = new BindLayerClass();
  bindLayerObject.LayerName = layerName;
  bindLayerObject.RefColumn1 = 3;
  bindLayerObject.RefColumn2 = 4;
  bindLayerObject.LayerType = BindLayerTypeConstants.miBindLayerTypeXY;
  CMapXDataset dataSet = axMap1.DataSets.Add(DatasetTypeConstants.miDataSetADO, rsNoPass, layerName, "ID", "layer", bindLayerObject, flds, false);
  //MapXLib.Dataset dataSet = axMap1.DataSets.Add(DatasetTypeConstants.miDataSetADO, rsNoPass, layerName, "ID", System.Reflection.Missing.Value, bindLayerObject, flds, false);
  CMapXLayer layer = axMap1.Layers._Item(layerName);
  layer.OverrideStyle = true;
  string picName = "icon.BMP";
  if (layer.Style.SupportsBitmapSymbols == true)
  {
  layer.Style.SymbolType = SymbolTypeConstants.miSymbolTypeBitmap;
  layer.Style.SymbolBitmapSize = 10;
  layer.Style.SymbolBitmapTransparent = true;
  layer.Style.SymbolBitmapName = picName;
  }  
  }


现在结果显示的只是一个点,疑惑!!
按照对这段代码的理解:CMapXDataset dataSet = axMap1.DataSets.Add(DatasetTypeConstants.miDataSetADO, rsNoPass, layerName, "ID", "layer", bindLayerObject, flds, false);
本该是查询“ID“ “layer” 作为ADODB.Recordset的关键字,显示数据库的所有点
难道理解有问题,还是代码有问题,需要修改

------解决方案--------------------
我把我在 vc下的代码贴出来你看看
C/C++ code
layer=axMap.Layers.Item(1);//获得图层//下面这段代码就这么写,我也搞不太懂,反正就是将图层的数据赋给layerVtCOleVariant layerVt;layerVt.vt = VT_DISPATCH;layerVt.pdispVal = layer.m_lpDispatch;layerVt.pdispVal->AddRef();ds = m_ctrlMapX.GetDatasets().Add(miDataSetLayer, layerVt);//然后你就可以循环读取 fieds了COleVariant ValueVt;int iFieldCount = ds.GetFields().GetCount();//显示每个fieldfor (int j = 0; j < iFieldCount; j++){buffer1 = ds.GetFields().Item(j+1).GetName();//字段COleVariant vVal;CString buffer1; vVal = ds.GetValue(f.GetFeatureID(), j+1);vVal.ChangeType(VT_BSTR);//转化为string类型buffer2 = vVal.bstrVal;//从相应类型的地方读取  字段的值}
------解决方案--------------------
不知道你要做什么,没仔细看代码 因为我不懂c# 如果把问题说清楚点 我可能会
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