缓冲区点查询（在地图上点击一点，查询一定范围内的信息）

首先在页面上添加如果代码：

<%--高亮显示--%>
DisplaySettings="visible=True:transparency=0:mime=True:imgFormat=PNG8:height=100:width=100:dpi=96:color=:transbg=False:displayInToc=True:dynamicTiling="
LayerDefinitions="" Name="Selection" />

<%--缓冲区--%>
DisplaySettings="visible=True:transparency=0:mime=True:imgFormat=PNG8:height=100:width=100:dpi=96:color=-16711872:transbg=False:displayInToc=True:dynamicTiling="
LayerDefinitions="" Name="Buffer" />

<%--查询地图--%>
DisplaySettings="visible=True:transparency=0:mime=True:imgFormat=PNG8:height=100:width=100:dpi=96:color=White:transbg=True:displayInToc=True:dynamicTiling="
LayerDefinitions="" Name="Portland" />

js 脚本：

//缓冲区查询
function fwsz()
{
document.getElementById("cxfwsz").style.display="block";
document.getElementById("BNResult").style.display="block";
var map = $find('Map1');
//画点函数
map.getGeometry(ESRI.ADF.Graphics.ShapeType.Point, usePoint, null, 'red', '#0000FF', 'pointer', true);

//获取鼠标点击的位置的地图坐标
function usePoint(clickPoint)
{
//地理坐标转到屏幕坐标
var screenPoint=map.toScreenPoint(clickPoint);
//获取屏幕坐标的X和Y分量
var screenX=screenPoint.offsetX;
var screenY=screenPoint.offsetY;
ToMapXY(screenX,screenY);
}
//屏幕坐标转到地理坐标
function ToMapXY(screenX,screenY)
{
var map = $find('Map1');
//返回 ESRI.ADF.Geometries.Point 类型的点
var mapPoint=map.toMapPoint(screenX,screenY);

var ddlcxfw=document.getElementById("ddlcxfw");

var cxfw=ddlcxfw.options[ddlcxfw.selectedIndex].text;

var message='ActiveType=center&EventArg=';
message+="States";
message+="&Condtion="+mapPoint+"&cxfw="+cxfw;
var context="Page1";
<%=attributeQueryCallBack %>
}
}

后台代码：

//属性查询
public string attributeQueryCallBack;

protected void Page_Load(object sender, EventArgs e)
{
attributeQueryCallBack = Page.ClientScript.GetCallbackEventReference(this, "message", "processCallbackResult", "context", "postBackError", true);
}

//ICallbackEventHandler先执行RaiseCallbackEvent方法
void ICallbackEventHandler.RaiseCallbackEvent(string eventArgument)
{
callbackArg = eventArgument;
}
string ICallbackEventHandler.GetCallbackResult()
{
string v = "";
//将传入参数依据&分割符分到querystring变量中
Array keyValuePairs = callbackArg.Split("&".ToCharArray());
NameValueCollection queryString = new NameValueCollection();
string[] keyValue;
if (keyValuePairs.Length > 0)
{
for (int i = 0; i < keyValuePairs.Length; i++)
{
keyValue = keyValuePairs.GetValue(i).ToString().Split("=".ToCharArray());
queryString.Add(keyValue[0], keyValue[1]);
}
}
else
{
keyValue = callbackArg.Split("=".ToCharArray());
if (keyValue.Length > 0)
queryString.Add(keyValue[0], keyValue[1]);
}
//针对参数中指定的ActiveType不同执行不同操作
string controlType = queryString["ActiveType"];
string eventArg = queryString["EventArg"];

//地图坐标
string condition = queryString["Condtion"];
switch (controlType)
{
case "center":

//查询范围，如1000米
string ddlcxfw = queryString["cxfw"];
string cxfw = ddlcxfw.Substring(0, ddlcxfw.Length - 1).ToString();
testhcq.hqctest(condition, cxfw, Map1);
v = Map1.CallbackResults.ToString();
break;
}

return v;
}

在app_code里添加testhcq类，类中添加hqctest，代码如下：

///

/// 缓冲区分析
///

/// 缓冲区查询点的地图坐标 x,y
/// 地图
public static void hqctest(string pointPosition, string cxfw, Map map)
{
int num = pointPosition.IndexOf(',');
if (num == -1)
return;
string[] str = pointPosition.Split(',');
float centerPointX = float.Parse(str[0]);
float centerPointY = float.Parse(str[1]);
float bufferdistance;
if (!Single.TryParse(cxfw, out bufferdistance))
{
bufferdistance = 0.0F;
}
//相互连接的直线或曲线
System.Drawing.Drawing2D.GraphicsPath gpath = new System.Drawing.Drawing2D.GraphicsPath();
//绘制椭圆
gpath.AddEllipse(centerPointX - (bufferdistance / 2), centerPointY - (bufferdistance / 2), bufferdistance, bufferdistance);
//Flatten的参数表示几何变换的3*3仿射矩阵
System.Drawing.Drawing2D.Matrix translateMatrix = new System.Drawing.Drawing2D.Matrix();

translateMatrix.Translate(0, 0);
//误差值,flatten的参数
float flattening = bufferdistance / 1000; //0.005F; //decimal degrees --- 100F; //meters,feet
//将gpath曲线转换成相连接的线段序列
gpath.Flatten(translateMatrix, flattening);
//点集合
ESRI.ArcGIS.ADF.Web.Geometry.PointCollection pc = new ESRI.ArcGIS.ADF.Web.Geometry.PointCollection();

foreach (System.Drawing.PointF dpnt in gpath.PathPoints)
{
pc.Add(new ESRI.ArcGIS.ADF.Web.Geometry.Point(dpnt.X, dpnt.Y));
}
//环形
ESRI.ArcGIS.ADF.Web.Geometry.Ring ring = new ESRI.ArcGIS.ADF.Web.Geometry.Ring();
ring.Points = pc;
ESRI.ArcGIS.ADF.Web.Geometry.RingCollection rings = new ESRI.ArcGIS.ADF.Web.Geometry.RingCollection();
rings.Add(ring);
ESRI.ArcGIS.ADF.Web.Geometry.Polygon mappoly = new ESRI.ArcGIS.ADF.Web.Geometry.Polygon();
mappoly.Rings = rings;
IdentifyHelper.IdentifyRectangle(map, mappoly);

#region
IEnumerable gfc = map.GetFunctionalities();
ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapResource gResource = null;
foreach (IGISFunctionality gfunc in gfc)
{
if (gfunc.Resource.Name == "Buffer")
{
gResource = (ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapResource)gfunc.Resource;
}
}
if (gResource == null)

throw new Exception("Buffer Graphics layer not in MapResourceManager");

//把缓冲区结果范围进行显示
ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer glayer = null;
//查找ElementGraphicsLayer在缓冲区中
foreach (System.Data.DataTable dt in gResource.Graphics.Tables)
{
if (dt is ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer)
{
glayer = (ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer)dt;
break;
}
}
//如果缓冲区中没有ElementGraphicsLayer就新增加一个ElementGraphicsLayer
if (glayer == null)
{
glayer = new ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer();
gResource.Graphics.Tables.Add(glayer);
}
//清除ElementGraphicsLayer中的内容
glayer.Clear();

ESRI.ArcGIS.ADF.Web.Geometry.Geometry geom = (ESRI.ArcGIS.ADF.Web.Geometry.Geometry)mappoly;
//设置点显示
ESRI.ArcGIS.ADF.Web.Display.Graphics.GraphicElement ge = new ESRI.ArcGIS.ADF.Web.Display.Graphics.GraphicElement(geom, System.Drawing.Color.Green);
//设置透明度
ge.Symbol.Transparency = 70.0;
//添加到缓冲区中进行显示
glayer.Add(ge);

string targetlayername = "SL_HLGQ_POLYGON ";
int resource_index = 2;

int layer_index = 0;
ESRI.ArcGIS.ADF.Web.DataSources.IMapFunctionality mf = (ESRI.ArcGIS.ADF.Web.DataSources.IMapFunctionality)map.GetFunctionality(resource_index);

ESRI.ArcGIS.ADF.Web.DataSources.IGISResource gisresource = mf.Resource;
bool supported = gisresource.SupportsFunctionality(typeof(ESRI.ArcGIS.ADF.Web.DataSources.IQueryFunctionality));
if (supported)
{

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

for (int i = 0; i < lnames.Length; i++)
{

if (lnames[i] == targetlayername)
{

layer_index = i;

break;

}

}

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

spatialfilter.ReturnADFGeometries = true;

spatialfilter.MaxRecords = 1000;

spatialfilter.Geometry = mappoly;

System.Data.DataSet ds = new DataSet();

System.Data.DataTable datatable = qfunc.Query(null, lids[layer_index], spatialfilter);

ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapResource selresource = null;

foreach (IGISFunctionality gfunc in gfc)
{

if (gfunc.Resource.Name == "Selection")
{

selresource = (ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapResource)gfunc.Resource;

}

}

if (selresource == null)

return;

ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer slayer = null;

foreach (System.Data.DataTable dt in selresource.Graphics.Tables)
{

if (dt is ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer)
{

slayer = (ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer)dt;

break;

}

}

if (slayer == null)
{

slayer = new ESRI.ArcGIS.ADF.Web.Display.Graphics.ElementGraphicsLayer();

selresource.Graphics.Tables.Add(slayer);

}

slayer.Clear();

DataRowCollection drs = datatable.Rows;

int shpind = -1;

for (int i = 0; i < datatable.Columns.Count; i++)
{

if (datatable.Columns[i].DataType == typeof(ESRI.ArcGIS.ADF.Web.Geometry.Geometry))
{

shpind = i;

break;

}

}

try
{

foreach (DataRow dr in drs)
{

ESRI.ArcGIS.ADF.Web.Geometry.Geometry sgeom = (ESRI.ArcGIS.ADF.Web.Geometry.Geometry)dr[shpind];

ESRI.ArcGIS.ADF.Web.Display.Graphics.GraphicElement sge = new ESRI.ArcGIS.ADF.Web.Display.Graphics.GraphicElement(sgeom, System.Drawing.Color.Red);

sge.Symbol.Transparency = 50.0;

slayer.Add(sge);

}

}

catch
{

throw new Exception("No geometry available in datatable");

}

GridView gdview = (GridView)map.Page.FindControl("GridView1");

object[] oa = new object[1];

string showtable = "'hidden'";

gdview.DataSource = dt;

gdview.DataBind();

 

string returnstring = null;

using (System.IO.StringWriter sw = new System.IO.StringWriter())
{

HtmlTextWriter htw = new HtmlTextWriter(sw);

gdview.RenderControl(htw);

htw.Flush();

returnstring = sw.ToString();

}
CallbackResult cr = new CallbackResult("div", "griddiv", "innercontent", returnstring);

map.CallbackResults.Add(cr);

showtable = "'visible'";

string sa = "var griddiv = document.getElementById('griddiv');";

sa += "griddiv.style.visibility = " + showtable + ";";

oa[0] = sa;

CallbackResult cr1 = new CallbackResult(null, null, "javascript", oa);

map.CallbackResults.Add(cr1);

 

if (map.ImageBlendingMode == ImageBlendingMode.WebTier)

{ map.Refresh(); }

else if (map.ImageBlendingMode == ImageBlendingMode.Browser)
{

map.RefreshResource(gResource.Name);

map.RefreshResource(selresource.Name);

}

}

}
#endregion

}

转载于:https://www.cnblogs.com/lff255356/archive/2012/10/26/2740982.html