用query实现图层信息的查询和定位功能

QueryTask和Query是arcgis server端已经封装好的服务,在flex的客户端只需要提供必要的参数即可执行查询,并返回数据以供操作。

本文主要是根据query的where条件执行查询,并实现图形的定位,高亮显示和属性信息的展示。

<esri:QueryTask id="queryTask"   url="{queryurl}"   useAMF="false" />
<esri:Query id="query" returnGeometry="true" where="{whereSql}"/>


首先查询会用到querytask和query,这2个标签的声明要放在<fx:Declarations>中,因为它只声明不展示。

protected function openGeometryByKey():void
{
if(graphicsLayer!=null)//定位前先清空graphicsLayer
graphicsLayer.clear();

//首先取得TreeNode节点SLID信息
var xml:XML = treeNodeObject as XML;
var strLabel:String=xml.attribute("lable")==null?"":StringUtil.trim(xml.attribute("lable").toString());
var slid:String=xml.attribute("slid")==null?"":StringUtil.trim(xml.attribute("slid").toString());

if(slid=="")
{
lablet.data="请检查业务是否上图,暂时无法定位该条信息";
return;
};
lablet.data="";
queryTask.url=configXML.serviceUrl;
this.whereSql="slid ='" + slid +"'";
queryTask.execute(query,new AsyncResponder(onResult, onFault));


function onResult(featureSet:FeatureSet, token:Object = null):void
{
resultCommand(featureSet,token,true);
}
function onResultEx(featureSet:FeatureSet, token:Object = null):void
{
resultCommand(featureSet,token,false);
}

function resultCommand(featureSet:FeatureSet, token:Object = null,isQuery04:Boolean=false):void
{
//查询成功,取得返回的图形信息开始定位
if(featureSet==null || featureSet.features==null ) return;
var graphic:Graphic=featureSet.features[0];
if(graphic==null) //若没有查到择到则到serviceUrl04中查询一次
{
if(isQuery04==true) //true为第一次查询,false为第二次
{
queryTask.url=configXML.serviceUrl04;
queryTask.execute(query,new AsyncResponder(onResultEx, onFault));
lablet.data="";
return;
}
lablet.data="请检查业务是否上图,暂时无法定位该条信息";
return;
}

map.infoWindow.hide();//先隐藏map的infowindow
graphicsLayer.clear();//先清空graphicsLayer

var mpt:MapPoint=null; //中心点
var goToExt:Extent=null; //图形的范围
for each (var myGraphic:Graphic in featureSet.features)//featureSet为查询返回的graphic数组
{
graphicsLayer.add(myGraphic); //将返回结果添加到graphicsLayer中
var geo:Geometry=myGraphic.geometry;//根据graphic的几何形状进行操作

switch (geo.type)
{
case Geometry.MAPPOINT://
{
mpt=geo as MapPoint;//绘制简单的点符号用于高亮显示
myGraphic.symbol=new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_CROSS, 15, 0xFF0000, 1);
break;
}

case Geometry.POLYLINE://线
{ //绘制简单的线符号用于高亮显示
myGraphic.symbol=new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID, 0xFF0000, 1.0, 3);
break;
}
case Geometry.POLYGON://
case Geometry.EXTENT:
{ //绘制简单的面符号用于高亮显示
var symbol:SimpleFillSymbol=new SimpleFillSymbol(SimpleFillSymbol.STYLE_SOLID, 0xFF0000, 0);
symbol.outline=new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID, 0xFF0000, 1.0, 3);
myGraphic.symbol=symbol;
break;
}
}

if(goToExt!=null&&geo.type!=Geometry.MAPPOINT)//若返回多个graphic则将其extent合并
{
goToExt=goToExt.union(geo.extent);
}
else
{
goToExt=geo.extent;
}
}
if (goToExt != null)//
{
map.extent=goToExt.expand(2);//实现map的定位
}
else//
{
var mapPoint:MapPoint=myGraphic.geometry as MapPoint;
map.centerAt(mapPoint);
}
if(goToExt!=null)//获取graphic的中心点mpt
{
mpt=goToExt.center;
}

map.infoWindow.label=strLabel;//实现属性窗口的展示
map.infoWindow.show(mpt);

}
function onFault(info:Object, token:Object = null):void
{
lablet.data="查询定位异常";
}
}








最后如果需要查询到的属性可以到myGraphic.attributes.QLR.toString();中获取

如下

map.infoWindow.label="                        宗地信息";
var vb:VBox=new VBox();
var qlr:mx.controls.Label=new mx.controls.Label();
var zdmj:mx.controls.Label=new mx.controls.Label();
var tdzl:mx.controls.Label=new mx.controls.Label();
var djh:mx.controls.Label=new mx.controls.Label();
var frdh:mx.controls.Label=new mx.controls.Label();
qlr.text="权利人:"+myGraphic.attributes.QLR.toString();
zdmj.text="宗地面积:"+myGraphic.attributes.QLR.toString();
tdzl.text="土地坐落:"+myGraphic.attributes.QLR.toString();
djh.text="地籍号:"+myGraphic.attributes.QLR.toString();
frdh.text="法人电话号:"+myGraphic.attributes.QLR.toString();
vb.addElement(qlr);
vb.addElement(zdmj);
vb.addElement(tdzl);
vb.addElement(djh);
vb.addElement(frdh);
map.infoWindow.contentGroup.addElement(vb);//组织inforwindow,并展示
map.infoWindow.show(mpt);
原文地址:https://www.cnblogs.com/tiandi/p/2275197.html