看两种不同的图层查询方法

方法一:

1 m_agsBase.InitializeVar(CsMap);//m_agsBase为通用类,初始化地图控件,获取各个参数

2

3 IMap pMap = m_agsBase.GetMap();

4

6

7

8

9

10 IServerContext pSOC = m_agsBase.GetSOC();

11 IQueryFilter pQueryFilter = (IQueryFilter)pSOC.CreateObject("esriGeodatabase.QueryFilter");

12 pQueryFilter.WhereClause = txtQuery.Text;

13

14 //取地图上的第一个图层

15 ILayer pLayer = pMap.get_Layer(2);

16 IFeatureLayer pFeatureLyr = pLayer as IFeatureLayer;

17 IFeatureClass pFeatCls = pFeatureLyr.FeatureClass;

18 IFeatureCursor pFeatCursor = pFeatCls.Search(pQueryFilter, false);

19

上面的方法的思路总结:基于底层进行属性查找,一方面由SoC生成IQueryFilter,另一方面生成 IFeatureLayer,两者结合使用方法:search,返回结果为 IFeatureCursor

方法二:

IEnumerable func_enum = null;

func_enum = CsMap.GetFunctionalities();

System.Data.DataTable mytable;

foreach (ESRI.ArcGIS.ADF.Web.DataSources.IMapFunctionality gisfunctionality in func_enum)

{

//gisresource = gisfunctionality.Resource;

//对特定的数据库图层进行查询

if (gisfunctionality.Resource.Name == "CsMap")

{ bool supported = false;

ESRI.ArcGIS.ADF.Web.DataSources.IGISResource gisresource = null;

gisresource = gisfunctionality.Resource;

supported = gisresource.SupportsFunctionality(typeof(ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality));

//如果支持

if (supported)

{

ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality qfunc;

qfunc = (ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality)gisresource.CreateFunctionality(typeof(ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality), null);

string[] lids;

string[] lnames;

qfunc.GetQueryableLayers(null, out lids, out lnames);

//对查询进行过滤

#region

ESRI.ArcGIS.ADF.Web.SpatialFilter spatialfilter = new ESRI.ArcGIS.ADF.Web.SpatialFilter();

spatialfilter.ReturnADFGeometries = false;

spatialfilter.MaxRecords = 1000;

spatialfilter.WhereClause = txtQuery.Text;

spatialfilter.Geometry = geometry;

#endregion

mytable = qfunc.Query(null, lids[2], spatialfilter);

方法二思路:1判断resource是否支持空间查询;

2生成queryfunction接口,并获取当前数据源中包含的可以查询的图层

3生成空间查询过滤器

4返回的结果为 Datatable

方法二是基于ADF框架的,而方法一是基于AO的