如何获取arcgis server发布的FeatureLayer图层中各要素,并根据名称着重标出该要素?

需求:已知根据数据后台查询到要素名称,想通过该名称查询要素多边形,不通过arcgis for jsp 提供的查询按钮实现。

这里只是一个demo,具体实施得结合自己的项目。

首先引入引用文件:

<link rel="stylesheet" href="https://js.arcgis.com/3.29/dijit/themes/tundra/tundra.css">
<link rel="stylesheet" href="https://js.arcgis.com/3.29/esri/css/esri.css">
<script src="https://js.arcgis.com/3.29/"></script>

接下来是添加arcgis api的引用函数及地图显示设置

 var map, dialog;
      require([
        "esri/map", "esri/layers/FeatureLayer",
        "esri/symbols/SimpleFillSymbol", "esri/symbols/SimpleLineSymbol",
        "esri/renderers/SimpleRenderer", "esri/graphic", "esri/lang",
        "esri/Color", "dojo/number", "dojo/dom-style",
        "dijit/TooltipDialog", "dijit/popup", "dojo/domReady!"
      ], function(
        Map, FeatureLayer,
        SimpleFillSymbol, SimpleLineSymbol,
        SimpleRenderer, Graphic, esriLang,
        Color, number, domStyle,
        TooltipDialog, dijitPopup
      ) {
        map = new Map("mapDiv", {
          basemap: "streets",
          center: [-80.94, 33.646],
          zoom: 8,
          slider: false
        });

然后添加要素图层,即FeatureLayer图层,这里面outFields用于过滤哪些字段,symbol为显示样式

var southCarolinaCounties = new FeatureLayer("https://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer/3", {
          mode: FeatureLayer.MODE_SNAPSHOT,
          outFields: ["NAME", "POP2000", "POP2007", "POP00_SQMI", "POP07_SQMI"]
        });
        southCarolinaCounties.setDefinitionExpression("STATE_NAME = 'South Carolina'");
        var symbol = new SimpleFillSymbol(
          SimpleFillSymbol.STYLE_SOLID,
          new SimpleLineSymbol(
            SimpleLineSymbol.STYLE_SOLID,
            new Color([255,255,255,0.35]),
            1
          ),
          new Color([125,125,125,0.35])
        );
        southCarolinaCounties.setRenderer(new SimpleRenderer(symbol));
        map.addLayer(southCarolinaCounties);

然后设定一个被选中要素的显示样式,即高亮显示的样式

var highlightSymbol = new SimpleFillSymbol(
          SimpleFillSymbol.STYLE_SOLID,
          new SimpleLineSymbol(
            SimpleLineSymbol.STYLE_SOLID,
            new Color([255,0,0]), 3
          ),
          new Color([125,125,125,0.35])
        );

接下面便是核心,即如何根据要素块的名称获取要素,并将该要素高亮显示,c表示整个FeatureLayer中地理要素,其中包括属性及空间位置,插件内部定义的

 map.on("load", function(){
  //我们需要用到的就是下面的代码
   var handle = southCarolinaCounties.on("update-end", function(){
    var c = southCarolinaCounties.graphics;
    //打印所有的要素块
    console.log(c);
    //定义需要找到的块名称
    var name = "Lee";
    //遍历所有的要素,找到该要素,在该要素位置新建一个高亮图层
    for(i=0;i<=c.length;i++){
     if(c[i].attributes.NAME == name){
      var highlightGraphic = new Graphic(c[i].geometry,highlightSymbol);
      map.graphics.add(highlightGraphic);   
     }
    }    
    //每次地图发生变换都会执行update-end事件,handle.remove()是为了避免代码被重复执行
    handle.remove();
   });
});

效果如下:
当name =“Lee”
如何获取arcgis server发布的FeatureLayer图层中各要素,并根据名称着重标出该要素?当name = “Cherokee”
如何获取arcgis server发布的FeatureLayer图层中各要素,并根据名称着重标出该要素?完整代码如下:
如何获取arcgis server发布的FeatureLayer图层中各要素,并根据名称着重标出该要素?如何获取arcgis server发布的FeatureLayer图层中各要素,并根据名称着重标出该要素?
如何获取arcgis server发布的FeatureLayer图层中各要素,并根据名称着重标出该要素?

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