/// <summary>
/// 在给定的点下，查询所有的活动的shapefile层
/// Queries all of the active shapefile layers for any within the specified tolerance of the given point.
/// </summary>
/// <param name="ProjX">要查询的相对于地图的x点坐标</param>
/// <param name="ProjY">要查询的相对于地图的y点坐标</param>
/// <param name="Tolerance">在所查询点坐标周围，允许的距离</param>
/// <returns>Returns an <c>IdentifiedLayers</c> object containing query results.</returns>
public MapWinGIS.Interfaces.IdentifiedLayers Identify(double ProjX, double ProjY, double Tolerance)
{
MainProgram.IdentifiedShapes identifyshpfile;
MainProgram.IdentifiedLayers ilyr = new MainProgram.IdentifiedLayers();
int i, j;
MapWinGIS.Shapefile shpfile;
object o, res = null;
MapWinGIS.Extents box;
int count = Program.frmMain.MapMain.NumLayers;
for (i = 0; i < count; i++) //遍历每一个图层
{
int lyrHandle = Program.frmMain.MapMain.get_LayerHandle(i);
if (Program.frmMain.MapMain.get_LayerVisible(lyrHandle)) //是可见的图层
{
o = Program.frmMain.MapMain.get_GetObject(lyrHandle);
if (o is MapWinGIS.Shapefile) //获取是shapefile类型的图层
{
shpfile = (MapWinGIS.Shapefile)o;
o = null;
box = new MapWinGIS.Extents();
box.SetBounds(ProjX, ProjY, 0, ProjX, ProjY, 0);
if (shpfile.SelectShapes(box, Tolerance, MapWinGIS.SelectMode.INTERSECTION, ref res)) //搜索该点，结果存在res中
{
identifyshpfile = new MainProgram.IdentifiedShapes();
Array arr;
arr = (Array)res; //得到在该点下的所有shape的索引集合
for (j = 0; j < arr.Length; j++)
{
identifyshpfile.Add((int)(arr.GetValue(j)));
}
ilyr.Add(identifyshpfile, lyrHandle);
}
}
}
}
return(ilyr);
}